Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-27 Thread Alyx
Why yes, yes there is. :) More of a distinction, in fact, than there is in
Linux world!

On Thu, Jan 26, 2012 at 9:02 AM, valdis.kletni...@vt.edu wrote:

 On Wed, 25 Jan 2012 17:54:02 PST, Alyx said:
  Are you looking at kernel code or userland code? (:

 Is there a clear distinction in the Windows world? :)

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-26 Thread Alyx
Are you looking at kernel code or userland code? (:

On Wed, Jan 25, 2012 at 2:35 AM, GloW - XD doo...@gmail.com wrote:

 INSECURE i mean*


 On 25 January 2012 21:30, Christian Sciberras uuf6...@gmail.com wrote:
  That's not necessarily true. On windows you can add custom
 clipboard formats
  that would contain a 'link' to the original source, causing the data
 to be
  actually
  passed when pasting. An example of this is when one copy+pastes a file.
  See the Windows Clipboard API for more info.
 
  Chris.
 
 
 
  On Wed, Jan 25, 2012 at 10:54 AM, Mario Vilas mvi...@gmail.com wrote:
 
  I'm not sure how the clipboard works in Linux desktops (I understand
  it's a little different), but at least in Windows environments data
  has to be copied to the clipboard when you hit Ctrl-C. It can't be
  copied when you hit Ctrl-V because then the applications wouldn't know
  if there is anything to paste (like you said, the button would be
  grayed).
 
  So to replicate this behavior it's necessary to send the data as it's
  copied, not as it's pasted. Most (not all, but most) desktop systems
  assume clipboard data can be freely shared with all applications and
  don't have any kind of isolation at all. VNC was designed with the
  same idea.
 
  The bottom line is, the problem here is using VNC for what Ben is
  using it. There are many more problems with that scenario and
  clipboard sharing may be the least of them.
 
  On Wed, Jan 25, 2012 at 8:44 AM, Peter Osterberg j...@vel.nu wrote:
   On 01/24/2012 07:18 PM, Mario Vilas wrote:
   Guys, could you please read carefully everything before you reply?
   I read carefully. It still didn't make sense, though.
  
   And you wouldn't be allowed to use copypaste while you edit
 sensitive
   documents either, I guess?
   I don't know how you could get to such a conclusion from what I
 wrote.
  
   You're reporting that if you copy and paste sensitive information and
   connect to a VNC session your clipboard data gets sent to the remote
   machine. That's pretty obvious and not a security hole that needs to
   be plugged.
  
   I don't think that is what Ben is saying. The clipboard get sent to
 the
   the server even before it is pasted, this happens without the user
   knowing of it.
  
   Notepad would have the paste button grayed otherwise, if the clipboard
   is empty, right? So it is already on the server before paste is
 pressed.
  
   So what ever was in the clipboard buffer is transmitted to the server
 on
   connection.
  
   This is at least the assumption I make from reading Ben's mails. Or...
   Is there a cliboard flag saying there is something on the clipboard,
 but
   it isn't transmitted until the user actually pastes? I haven't really
   got any experience with how the clipboard feature is implemented. My
   assumption is however that it has to be on server for notepad to be
   aware that Paste shouldn't be grayed out...
  
   I think Ben's report make complete sense actually, it would be better
 to
   have the clipboard feature as a default. Security before features...
 =)
  
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   Full-Disclosure - We believe in it.
   Charter: http://lists.grok.org.uk/full-disclosure-charter.html
   Hosted and sponsored by Secunia - http://secunia.com/
 
 
 
  --
  “There's a reason we separate military and the police: one fights the
  enemy of the state, the other serves and protects the people. When the
  military becomes both, then the enemies of the state tend to become
  the people.”
 
  ___
  Full-Disclosure - We believe in it.
  Charter: http://lists.grok.org.uk/full-disclosure-charter.html
  Hosted and sponsored by Secunia - http://secunia.com/
 
 
 
  ___
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  Charter: http://lists.grok.org.uk/full-disclosure-charter.html
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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-26 Thread Valdis . Kletnieks
On Wed, 25 Jan 2012 17:54:02 PST, Alyx said:
 Are you looking at kernel code or userland code? (:

Is there a clear distinction in the Windows world? :)


pgpD56WqAeNhf.pgp
Description: PGP signature
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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-26 Thread phocean
Yes :|

-- 
phocean 0...@phocean.net

Le jeudi 26 janvier 2012 à 12:02 -0500, valdis.kletni...@vt.edu a
écrit :
 On Wed, 25 Jan 2012 17:54:02 PST, Alyx said:
  Are you looking at kernel code or userland code? (:
 
 Is there a clear distinction in the Windows world? :)
 ___
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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Peter Osterberg
On 01/24/2012 07:18 PM, Mario Vilas wrote:
 Guys, could you please read carefully everything before you reply?
 I read carefully. It still didn't make sense, though.

 And you wouldn't be allowed to use copypaste while you edit sensitive
 documents either, I guess?
 I don't know how you could get to such a conclusion from what I wrote.

 You're reporting that if you copy and paste sensitive information and
 connect to a VNC session your clipboard data gets sent to the remote
 machine. That's pretty obvious and not a security hole that needs to
 be plugged.

I don't think that is what Ben is saying. The clipboard get sent to the
the server even before it is pasted, this happens without the user
knowing of it.

Notepad would have the paste button grayed otherwise, if the clipboard
is empty, right? So it is already on the server before paste is pressed.

So what ever was in the clipboard buffer is transmitted to the server on
connection.

This is at least the assumption I make from reading Ben's mails. Or...
Is there a cliboard flag saying there is something on the clipboard, but
it isn't transmitted until the user actually pastes? I haven't really
got any experience with how the clipboard feature is implemented. My
assumption is however that it has to be on server for notepad to be
aware that Paste shouldn't be grayed out...

I think Ben's report make complete sense actually, it would be better to
have the clipboard feature as a default. Security before features... =)

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Peter Osterberg
have the clipboard disabled...

On 01/25/2012 08:44 AM, Peter Osterberg wrote:
 I think Ben's report make complete sense actually, it would be better to
 have the clipboard feature as a default. Security before features... =)

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Dan Yefimov
On 25.01.2012 5:45, Ben Bucksch wrote:
 On 25.01.2012 00:52, Henri Salo wrote:
 On Wed, Jan 25, 2012 at 12:47:28AM +0100, Ben Bucksch wrote:
 On 25.01.2012 00:09, Dan Kaminsky wrote:
 IP KVM, in which the foreign server basically gets only inbound
 Keyboard and Mouse and outbound uncompressed pixels.
 That is *precisely* what VNC is: an open-source IP KVM.
 What the hell? Seriously..

 http://en.wikipedia.org/wiki/VNC

 hihi. Thanks.

 It transmits the keyboard and mouse events from one computer to
 another, relaying the graphical screen updates back in the other
 direction, over a network.
 The VNC protocol (RFB) is very simple, based on one graphic primitive
 from server to client ('Put a rectangle of pixel data at the specified
 X,Y position') and event messages from client to server.

 Compare to above.

 Now, the part where it defines that clipboard is also a standard part of
 VNC... oh, huch, it's not there! (Just a random note that Unicode is
 impossible, but not that clipboard is defined as part of the protocol at
 all.) Ah, I know... Surely, it must be on
 http://en.wikipedia.org/wiki/RFB_protocol... No, same thing there.
 Strange.

It should be strictly understood that something not being mentioned in the 
Wikipedia article doesn't mean that doesn't exist at all, since Wikipedia is 
_not_ authoritative information source. The authoritative information source 
would be the formal specification of the protocol explicitly defining the set 
of 
event types and explicitly prohibiting non-defined event types, otherwise 
implementations are free to define and use their own event types being in fact 
extensions of the protocol. It's defined nowhere that VNC is _exactly_ 
open-source IP KVM and nothing more.

 P.S. I was just reporting bug. I hope at least some software finds a
 better solution. Have fun.

I'd suggest you find alternative product allowing you to explicitly configure 
that clipboard is not transmitted to the host under control instead of 
struggling with the product limitations and design flaws.
-- 

Sincerely Yours, Dan.

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread GloW - XD
you are seriously more retarded than even the n3td3v+me+you
together...damn army..!


On 25 January 2012 19:29, Peter Osterberg j...@vel.nu wrote:
 Wasn't the original thread originally about VNC?

 On 01/25/2012 09:27 AM, GloW - XD wrote:
 derp, do you know what KVM IP is ?
 readup on how that relays ;)
 thats that.
 XD


 On 25 January 2012 18:44, Peter Osterberg j...@vel.nu wrote:
 On 01/24/2012 07:18 PM, Mario Vilas wrote:
 Guys, could you please read carefully everything before you reply?
 I read carefully. It still didn't make sense, though.

 And you wouldn't be allowed to use copypaste while you edit sensitive
 documents either, I guess?
 I don't know how you could get to such a conclusion from what I wrote.

 You're reporting that if you copy and paste sensitive information and
 connect to a VNC session your clipboard data gets sent to the remote
 machine. That's pretty obvious and not a security hole that needs to
 be plugged.
 I don't think that is what Ben is saying. The clipboard get sent to the
 the server even before it is pasted, this happens without the user
 knowing of it.

 Notepad would have the paste button grayed otherwise, if the clipboard
 is empty, right? So it is already on the server before paste is pressed.

 So what ever was in the clipboard buffer is transmitted to the server on
 connection.

 This is at least the assumption I make from reading Ben's mails. Or...
 Is there a cliboard flag saying there is something on the clipboard, but
 it isn't transmitted until the user actually pastes? I haven't really
 got any experience with how the clipboard feature is implemented. My
 assumption is however that it has to be on server for notepad to be
 aware that Paste shouldn't be grayed out...

 I think Ben's report make complete sense actually, it would be better to
 have the clipboard feature as a default. Security before features... =)

 ___
 Full-Disclosure - We believe in it.
 Charter: http://lists.grok.org.uk/full-disclosure-charter.html
 Hosted and sponsored by Secunia - http://secunia.com/

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread GloW - XD
nice to send THIS one to fd, and you ssomehow admit to knowing it here
yet, i told you what it was, exactly, dont try make me look bad fag,
or i will drop your fucking domain, for a month :)
ciao beech,.
xd


On 25 January 2012 19:55, Dan Yefimov d...@lightwave.net.ru wrote:
 On 25.01.2012 5:45, Ben Bucksch wrote:
 On 25.01.2012 00:52, Henri Salo wrote:
 On Wed, Jan 25, 2012 at 12:47:28AM +0100, Ben Bucksch wrote:
 On 25.01.2012 00:09, Dan Kaminsky wrote:
 IP KVM, in which the foreign server basically gets only inbound
 Keyboard and Mouse and outbound uncompressed pixels.
 That is *precisely* what VNC is: an open-source IP KVM.
 What the hell? Seriously..

 http://en.wikipedia.org/wiki/VNC

 hihi. Thanks.

 It transmits the keyboard and mouse events from one computer to
 another, relaying the graphical screen updates back in the other
 direction, over a network.
 The VNC protocol (RFB) is very simple, based on one graphic primitive
 from server to client ('Put a rectangle of pixel data at the specified
 X,Y position') and event messages from client to server.

 Compare to above.

 Now, the part where it defines that clipboard is also a standard part of
 VNC... oh, huch, it's not there! (Just a random note that Unicode is
 impossible, but not that clipboard is defined as part of the protocol at
 all.) Ah, I know... Surely, it must be on
 http://en.wikipedia.org/wiki/RFB_protocol... No, same thing there.
 Strange.

 It should be strictly understood that something not being mentioned in the
 Wikipedia article doesn't mean that doesn't exist at all, since Wikipedia is
 _not_ authoritative information source. The authoritative information source
 would be the formal specification of the protocol explicitly defining the set 
 of
 event types and explicitly prohibiting non-defined event types, otherwise
 implementations are free to define and use their own event types being in fact
 extensions of the protocol. It's defined nowhere that VNC is _exactly_
 open-source IP KVM and nothing more.

 P.S. I was just reporting bug. I hope at least some software finds a
 better solution. Have fun.

 I'd suggest you find alternative product allowing you to explicitly configure
 that clipboard is not transmitted to the host under control instead of
 struggling with the product limitations and design flaws.
 --

 Sincerely Yours, Dan.

 ___
 Full-Disclosure - We believe in it.
 Charter: http://lists.grok.org.uk/full-disclosure-charter.html
 Hosted and sponsored by Secunia - http://secunia.com/

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Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread GloW - XD
ooops my bad, wriong guy, or, you dont understand this either ?


On 25 January 2012 19:55, Dan Yefimov d...@lightwave.net.ru wrote:
 On 25.01.2012 5:45, Ben Bucksch wrote:
 On 25.01.2012 00:52, Henri Salo wrote:
 On Wed, Jan 25, 2012 at 12:47:28AM +0100, Ben Bucksch wrote:
 On 25.01.2012 00:09, Dan Kaminsky wrote:
 IP KVM, in which the foreign server basically gets only inbound
 Keyboard and Mouse and outbound uncompressed pixels.
 That is *precisely* what VNC is: an open-source IP KVM.
 What the hell? Seriously..

 http://en.wikipedia.org/wiki/VNC

 hihi. Thanks.

 It transmits the keyboard and mouse events from one computer to
 another, relaying the graphical screen updates back in the other
 direction, over a network.
 The VNC protocol (RFB) is very simple, based on one graphic primitive
 from server to client ('Put a rectangle of pixel data at the specified
 X,Y position') and event messages from client to server.

 Compare to above.

 Now, the part where it defines that clipboard is also a standard part of
 VNC... oh, huch, it's not there! (Just a random note that Unicode is
 impossible, but not that clipboard is defined as part of the protocol at
 all.) Ah, I know... Surely, it must be on
 http://en.wikipedia.org/wiki/RFB_protocol... No, same thing there.
 Strange.

 It should be strictly understood that something not being mentioned in the
 Wikipedia article doesn't mean that doesn't exist at all, since Wikipedia is
 _not_ authoritative information source. The authoritative information source
 would be the formal specification of the protocol explicitly defining the set 
 of
 event types and explicitly prohibiting non-defined event types, otherwise
 implementations are free to define and use their own event types being in fact
 extensions of the protocol. It's defined nowhere that VNC is _exactly_
 open-source IP KVM and nothing more.

 P.S. I was just reporting bug. I hope at least some software finds a
 better solution. Have fun.

 I'd suggest you find alternative product allowing you to explicitly configure
 that clipboard is not transmitted to the host under control instead of
 struggling with the product limitations and design flaws.
 --

 Sincerely Yours, Dan.

 ___
 Full-Disclosure - We believe in it.
 Charter: http://lists.grok.org.uk/full-disclosure-charter.html
 Hosted and sponsored by Secunia - http://secunia.com/

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Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Peter Osterberg
I could never lower myself to your level so I guess you win

On 01/25/2012 10:32 AM, GloW - XD wrote:
 you are seriously more retarded than even the n3td3v+me+you
 together...damn army..!


 On 25 January 2012 19:29, Peter Osterberg j...@vel.nu wrote:
 Wasn't the original thread originally about VNC?

 On 01/25/2012 09:27 AM, GloW - XD wrote:
 derp, do you know what KVM IP is ?
 readup on how that relays ;)
 thats that.
 XD


 On 25 January 2012 18:44, Peter Osterberg j...@vel.nu wrote:
 On 01/24/2012 07:18 PM, Mario Vilas wrote:
 Guys, could you please read carefully everything before you reply?
 I read carefully. It still didn't make sense, though.

 And you wouldn't be allowed to use copypaste while you edit sensitive
 documents either, I guess?
 I don't know how you could get to such a conclusion from what I wrote.

 You're reporting that if you copy and paste sensitive information and
 connect to a VNC session your clipboard data gets sent to the remote
 machine. That's pretty obvious and not a security hole that needs to
 be plugged.
 I don't think that is what Ben is saying. The clipboard get sent to the
 the server even before it is pasted, this happens without the user
 knowing of it.

 Notepad would have the paste button grayed otherwise, if the clipboard
 is empty, right? So it is already on the server before paste is pressed.

 So what ever was in the clipboard buffer is transmitted to the server on
 connection.

 This is at least the assumption I make from reading Ben's mails. Or...
 Is there a cliboard flag saying there is something on the clipboard, but
 it isn't transmitted until the user actually pastes? I haven't really
 got any experience with how the clipboard feature is implemented. My
 assumption is however that it has to be on server for notepad to be
 aware that Paste shouldn't be grayed out...

 I think Ben's report make complete sense actually, it would be better to
 have the clipboard feature as a default. Security before features... =)

 ___
 Full-Disclosure - We believe in it.
 Charter: http://lists.grok.org.uk/full-disclosure-charter.html
 Hosted and sponsored by Secunia - http://secunia.com/

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Mario Vilas
 IP KVM, in which the foreign server basically gets only inbound
 Keyboard and Mouse and outbound uncompressed pixels.

 That is *precisely* what VNC is: an open-source IP KVM.

No, it's not. I won't go into the differences because other people
already did in this thread.

 And please don't turn this into you're stupid, because I've seen
 others with the same setup. As mentioned, I know of a government agency
 with highly competent IT staff who had a similar setup: normal and
 sensitive work is on the desktop/notebook and Internet access (which is
 considered insecure) is on a remote machine, with a viewer on the desktop.

That proves nothing. For example, there are many SCADA devices owned
by government agencies  connected to the Internet, but that doesn't
mean it's a good idea to do so.

-- 
“There's a reason we separate military and the police: one fights the
enemy of the state, the other serves and protects the people. When the
military becomes both, then the enemies of the state tend to become
the people.”

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Charter: http://lists.grok.org.uk/full-disclosure-charter.html
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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Mario Vilas
I'm not sure how the clipboard works in Linux desktops (I understand
it's a little different), but at least in Windows environments data
has to be copied to the clipboard when you hit Ctrl-C. It can't be
copied when you hit Ctrl-V because then the applications wouldn't know
if there is anything to paste (like you said, the button would be
grayed).

So to replicate this behavior it's necessary to send the data as it's
copied, not as it's pasted. Most (not all, but most) desktop systems
assume clipboard data can be freely shared with all applications and
don't have any kind of isolation at all. VNC was designed with the
same idea.

The bottom line is, the problem here is using VNC for what Ben is
using it. There are many more problems with that scenario and
clipboard sharing may be the least of them.

On Wed, Jan 25, 2012 at 8:44 AM, Peter Osterberg j...@vel.nu wrote:
 On 01/24/2012 07:18 PM, Mario Vilas wrote:
 Guys, could you please read carefully everything before you reply?
 I read carefully. It still didn't make sense, though.

 And you wouldn't be allowed to use copypaste while you edit sensitive
 documents either, I guess?
 I don't know how you could get to such a conclusion from what I wrote.

 You're reporting that if you copy and paste sensitive information and
 connect to a VNC session your clipboard data gets sent to the remote
 machine. That's pretty obvious and not a security hole that needs to
 be plugged.

 I don't think that is what Ben is saying. The clipboard get sent to the
 the server even before it is pasted, this happens without the user
 knowing of it.

 Notepad would have the paste button grayed otherwise, if the clipboard
 is empty, right? So it is already on the server before paste is pressed.

 So what ever was in the clipboard buffer is transmitted to the server on
 connection.

 This is at least the assumption I make from reading Ben's mails. Or...
 Is there a cliboard flag saying there is something on the clipboard, but
 it isn't transmitted until the user actually pastes? I haven't really
 got any experience with how the clipboard feature is implemented. My
 assumption is however that it has to be on server for notepad to be
 aware that Paste shouldn't be grayed out...

 I think Ben's report make complete sense actually, it would be better to
 have the clipboard feature as a default. Security before features... =)

 ___
 Full-Disclosure - We believe in it.
 Charter: http://lists.grok.org.uk/full-disclosure-charter.html
 Hosted and sponsored by Secunia - http://secunia.com/



-- 
“There's a reason we separate military and the police: one fights the
enemy of the state, the other serves and protects the people. When the
military becomes both, then the enemies of the state tend to become
the people.”

___
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/


Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Mario Vilas
Fair enough :)

On Wed, Jan 25, 2012 at 10:59 AM, Peter Osterberg j...@vel.nu wrote:


 On 01/25/2012 10:54 AM, Mario Vilas wrote:
 The bottom line is, the problem here is using VNC for what Ben is
 using it. There are many more problems with that scenario and
 clipboard sharing may be the least of them.
 That may very well be true. I am not trying to debate that.





-- 
“There's a reason we separate military and the police: one fights the
enemy of the state, the other serves and protects the people. When the
military becomes both, then the enemies of the state tend to become
the people.”

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Peter Osterberg


On 01/25/2012 10:54 AM, Mario Vilas wrote:
 The bottom line is, the problem here is using VNC for what Ben is
 using it. There are many more problems with that scenario and
 clipboard sharing may be the least of them.
That may very well be true. I am not trying to debate that.


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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Christian Sciberras
That's not necessarily true. On windows you can add custom clipboard formats
that would contain a 'link' to the original source, causing the data to be
actually
passed when pasting. An example of this is when one copy+pastes a file.
See the Windows Clipboard API for more info.

Chris.



On Wed, Jan 25, 2012 at 10:54 AM, Mario Vilas mvi...@gmail.com wrote:

 I'm not sure how the clipboard works in Linux desktops (I understand
 it's a little different), but at least in Windows environments data
 has to be copied to the clipboard when you hit Ctrl-C. It can't be
 copied when you hit Ctrl-V because then the applications wouldn't know
 if there is anything to paste (like you said, the button would be
 grayed).

 So to replicate this behavior it's necessary to send the data as it's
 copied, not as it's pasted. Most (not all, but most) desktop systems
 assume clipboard data can be freely shared with all applications and
 don't have any kind of isolation at all. VNC was designed with the
 same idea.

 The bottom line is, the problem here is using VNC for what Ben is
 using it. There are many more problems with that scenario and
 clipboard sharing may be the least of them.

 On Wed, Jan 25, 2012 at 8:44 AM, Peter Osterberg j...@vel.nu wrote:
  On 01/24/2012 07:18 PM, Mario Vilas wrote:
  Guys, could you please read carefully everything before you reply?
  I read carefully. It still didn't make sense, though.
 
  And you wouldn't be allowed to use copypaste while you edit sensitive
  documents either, I guess?
  I don't know how you could get to such a conclusion from what I wrote.
 
  You're reporting that if you copy and paste sensitive information and
  connect to a VNC session your clipboard data gets sent to the remote
  machine. That's pretty obvious and not a security hole that needs to
  be plugged.
 
  I don't think that is what Ben is saying. The clipboard get sent to the
  the server even before it is pasted, this happens without the user
  knowing of it.
 
  Notepad would have the paste button grayed otherwise, if the clipboard
  is empty, right? So it is already on the server before paste is pressed.
 
  So what ever was in the clipboard buffer is transmitted to the server on
  connection.
 
  This is at least the assumption I make from reading Ben's mails. Or...
  Is there a cliboard flag saying there is something on the clipboard, but
  it isn't transmitted until the user actually pastes? I haven't really
  got any experience with how the clipboard feature is implemented. My
  assumption is however that it has to be on server for notepad to be
  aware that Paste shouldn't be grayed out...
 
  I think Ben's report make complete sense actually, it would be better to
  have the clipboard feature as a default. Security before features... =)
 
  ___
  Full-Disclosure - We believe in it.
  Charter: http://lists.grok.org.uk/full-disclosure-charter.html
  Hosted and sponsored by Secunia - http://secunia.com/



 --
 “There's a reason we separate military and the police: one fights the
 enemy of the state, the other serves and protects the people. When the
 military becomes both, then the enemies of the state tend to become
 the people.”

 ___
 Full-Disclosure - We believe in it.
 Charter: http://lists.grok.org.uk/full-disclosure-charter.html
 Hosted and sponsored by Secunia - http://secunia.com/

___
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/

Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread GloW - XD
Windows is even more secure, have you actually, read any of the code /


On 25 January 2012 21:30, Christian Sciberras uuf6...@gmail.com wrote:
 That's not necessarily true. On windows you can add custom clipboard formats
 that would contain a 'link' to the original source, causing the data to be
 actually
 passed when pasting. An example of this is when one copy+pastes a file.
 See the Windows Clipboard API for more info.

 Chris.



 On Wed, Jan 25, 2012 at 10:54 AM, Mario Vilas mvi...@gmail.com wrote:

 I'm not sure how the clipboard works in Linux desktops (I understand
 it's a little different), but at least in Windows environments data
 has to be copied to the clipboard when you hit Ctrl-C. It can't be
 copied when you hit Ctrl-V because then the applications wouldn't know
 if there is anything to paste (like you said, the button would be
 grayed).

 So to replicate this behavior it's necessary to send the data as it's
 copied, not as it's pasted. Most (not all, but most) desktop systems
 assume clipboard data can be freely shared with all applications and
 don't have any kind of isolation at all. VNC was designed with the
 same idea.

 The bottom line is, the problem here is using VNC for what Ben is
 using it. There are many more problems with that scenario and
 clipboard sharing may be the least of them.

 On Wed, Jan 25, 2012 at 8:44 AM, Peter Osterberg j...@vel.nu wrote:
  On 01/24/2012 07:18 PM, Mario Vilas wrote:
  Guys, could you please read carefully everything before you reply?
  I read carefully. It still didn't make sense, though.
 
  And you wouldn't be allowed to use copypaste while you edit sensitive
  documents either, I guess?
  I don't know how you could get to such a conclusion from what I wrote.
 
  You're reporting that if you copy and paste sensitive information and
  connect to a VNC session your clipboard data gets sent to the remote
  machine. That's pretty obvious and not a security hole that needs to
  be plugged.
 
  I don't think that is what Ben is saying. The clipboard get sent to the
  the server even before it is pasted, this happens without the user
  knowing of it.
 
  Notepad would have the paste button grayed otherwise, if the clipboard
  is empty, right? So it is already on the server before paste is pressed.
 
  So what ever was in the clipboard buffer is transmitted to the server on
  connection.
 
  This is at least the assumption I make from reading Ben's mails. Or...
  Is there a cliboard flag saying there is something on the clipboard, but
  it isn't transmitted until the user actually pastes? I haven't really
  got any experience with how the clipboard feature is implemented. My
  assumption is however that it has to be on server for notepad to be
  aware that Paste shouldn't be grayed out...
 
  I think Ben's report make complete sense actually, it would be better to
  have the clipboard feature as a default. Security before features... =)
 
  ___
  Full-Disclosure - We believe in it.
  Charter: http://lists.grok.org.uk/full-disclosure-charter.html
  Hosted and sponsored by Secunia - http://secunia.com/



 --
 “There's a reason we separate military and the police: one fights the
 enemy of the state, the other serves and protects the people. When the
 military becomes both, then the enemies of the state tend to become
 the people.”

 ___
 Full-Disclosure - We believe in it.
 Charter: http://lists.grok.org.uk/full-disclosure-charter.html
 Hosted and sponsored by Secunia - http://secunia.com/



 ___
 Full-Disclosure - We believe in it.
 Charter: http://lists.grok.org.uk/full-disclosure-charter.html
 Hosted and sponsored by Secunia - http://secunia.com/

___
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/


Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread GloW - XD
INSECURE i mean*


On 25 January 2012 21:30, Christian Sciberras uuf6...@gmail.com wrote:
 That's not necessarily true. On windows you can add custom clipboard formats
 that would contain a 'link' to the original source, causing the data to be
 actually
 passed when pasting. An example of this is when one copy+pastes a file.
 See the Windows Clipboard API for more info.

 Chris.



 On Wed, Jan 25, 2012 at 10:54 AM, Mario Vilas mvi...@gmail.com wrote:

 I'm not sure how the clipboard works in Linux desktops (I understand
 it's a little different), but at least in Windows environments data
 has to be copied to the clipboard when you hit Ctrl-C. It can't be
 copied when you hit Ctrl-V because then the applications wouldn't know
 if there is anything to paste (like you said, the button would be
 grayed).

 So to replicate this behavior it's necessary to send the data as it's
 copied, not as it's pasted. Most (not all, but most) desktop systems
 assume clipboard data can be freely shared with all applications and
 don't have any kind of isolation at all. VNC was designed with the
 same idea.

 The bottom line is, the problem here is using VNC for what Ben is
 using it. There are many more problems with that scenario and
 clipboard sharing may be the least of them.

 On Wed, Jan 25, 2012 at 8:44 AM, Peter Osterberg j...@vel.nu wrote:
  On 01/24/2012 07:18 PM, Mario Vilas wrote:
  Guys, could you please read carefully everything before you reply?
  I read carefully. It still didn't make sense, though.
 
  And you wouldn't be allowed to use copypaste while you edit sensitive
  documents either, I guess?
  I don't know how you could get to such a conclusion from what I wrote.
 
  You're reporting that if you copy and paste sensitive information and
  connect to a VNC session your clipboard data gets sent to the remote
  machine. That's pretty obvious and not a security hole that needs to
  be plugged.
 
  I don't think that is what Ben is saying. The clipboard get sent to the
  the server even before it is pasted, this happens without the user
  knowing of it.
 
  Notepad would have the paste button grayed otherwise, if the clipboard
  is empty, right? So it is already on the server before paste is pressed.
 
  So what ever was in the clipboard buffer is transmitted to the server on
  connection.
 
  This is at least the assumption I make from reading Ben's mails. Or...
  Is there a cliboard flag saying there is something on the clipboard, but
  it isn't transmitted until the user actually pastes? I haven't really
  got any experience with how the clipboard feature is implemented. My
  assumption is however that it has to be on server for notepad to be
  aware that Paste shouldn't be grayed out...
 
  I think Ben's report make complete sense actually, it would be better to
  have the clipboard feature as a default. Security before features... =)
 
  ___
  Full-Disclosure - We believe in it.
  Charter: http://lists.grok.org.uk/full-disclosure-charter.html
  Hosted and sponsored by Secunia - http://secunia.com/



 --
 “There's a reason we separate military and the police: one fights the
 enemy of the state, the other serves and protects the people. When the
 military becomes both, then the enemies of the state tend to become
 the people.”

 ___
 Full-Disclosure - We believe in it.
 Charter: http://lists.grok.org.uk/full-disclosure-charter.html
 Hosted and sponsored by Secunia - http://secunia.com/



 ___
 Full-Disclosure - We believe in it.
 Charter: http://lists.grok.org.uk/full-disclosure-charter.html
 Hosted and sponsored by Secunia - http://secunia.com/

___
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/


Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Christian Sciberras
No, I only read the manual.

Now go troll somwhere else. :)

On Wed, Jan 25, 2012 at 11:35 AM, GloW - XD doo...@gmail.com wrote:

 Windows is even more secure, have you actually, read any of the code /


 On 25 January 2012 21:30, Christian Sciberras uuf6...@gmail.com wrote:
  That's not necessarily true. On windows you can add custom
 clipboard formats
  that would contain a 'link' to the original source, causing the data
 to be
  actually
  passed when pasting. An example of this is when one copy+pastes a file.
  See the Windows Clipboard API for more info.
 
  Chris.
 
 
 
  On Wed, Jan 25, 2012 at 10:54 AM, Mario Vilas mvi...@gmail.com wrote:
 
  I'm not sure how the clipboard works in Linux desktops (I understand
  it's a little different), but at least in Windows environments data
  has to be copied to the clipboard when you hit Ctrl-C. It can't be
  copied when you hit Ctrl-V because then the applications wouldn't know
  if there is anything to paste (like you said, the button would be
  grayed).
 
  So to replicate this behavior it's necessary to send the data as it's
  copied, not as it's pasted. Most (not all, but most) desktop systems
  assume clipboard data can be freely shared with all applications and
  don't have any kind of isolation at all. VNC was designed with the
  same idea.
 
  The bottom line is, the problem here is using VNC for what Ben is
  using it. There are many more problems with that scenario and
  clipboard sharing may be the least of them.
 
  On Wed, Jan 25, 2012 at 8:44 AM, Peter Osterberg j...@vel.nu wrote:
   On 01/24/2012 07:18 PM, Mario Vilas wrote:
   Guys, could you please read carefully everything before you reply?
   I read carefully. It still didn't make sense, though.
  
   And you wouldn't be allowed to use copypaste while you edit
 sensitive
   documents either, I guess?
   I don't know how you could get to such a conclusion from what I
 wrote.
  
   You're reporting that if you copy and paste sensitive information and
   connect to a VNC session your clipboard data gets sent to the remote
   machine. That's pretty obvious and not a security hole that needs to
   be plugged.
  
   I don't think that is what Ben is saying. The clipboard get sent to
 the
   the server even before it is pasted, this happens without the user
   knowing of it.
  
   Notepad would have the paste button grayed otherwise, if the clipboard
   is empty, right? So it is already on the server before paste is
 pressed.
  
   So what ever was in the clipboard buffer is transmitted to the server
 on
   connection.
  
   This is at least the assumption I make from reading Ben's mails. Or...
   Is there a cliboard flag saying there is something on the clipboard,
 but
   it isn't transmitted until the user actually pastes? I haven't really
   got any experience with how the clipboard feature is implemented. My
   assumption is however that it has to be on server for notepad to be
   aware that Paste shouldn't be grayed out...
  
   I think Ben's report make complete sense actually, it would be better
 to
   have the clipboard feature as a default. Security before features...
 =)
  
   ___
   Full-Disclosure - We believe in it.
   Charter: http://lists.grok.org.uk/full-disclosure-charter.html
   Hosted and sponsored by Secunia - http://secunia.com/
 
 
 
  --
  “There's a reason we separate military and the police: one fights the
  enemy of the state, the other serves and protects the people. When the
  military becomes both, then the enemies of the state tend to become
  the people.”
 
  ___
  Full-Disclosure - We believe in it.
  Charter: http://lists.grok.org.uk/full-disclosure-charter.html
  Hosted and sponsored by Secunia - http://secunia.com/
 
 
 
  ___
  Full-Disclosure - We believe in it.
  Charter: http://lists.grok.org.uk/full-disclosure-charter.html
  Hosted and sponsored by Secunia - http://secunia.com/

___
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/

Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Ben Bucksch
On 25.01.2012 08:44, Peter Osterberg wrote:
 I don't think that is what Ben is saying. The clipboard get sent to the
 the server even before it is pasted, this happens without the user
 knowing of it.

 Notepad would have the paste button grayed otherwise, if the clipboard
 is empty, right? So it is already on the server before paste is pressed.

Exactly. I take offense in that without the user knowing it part.

I chose my reproduction specifically with a mouse action and not Ctrl-V 
so that the VNC viewer cannot know I tried to paste in notepad.exe and 
cannot have transmitted the information at that moment only. It means 
that Windows had the information all along, at the moment when I copied, 
which means the remote Windows reads all my copies on the local X11, not 
just when I paste in Windows. That and only that is the problem.


Possible solution, concretely:
Paste button on VNC viewer toolbar
If the user presses the button, the viewer sends the clipboard to the 
remote machine at that moment, and then triggers a Ctrl-V keypress in 
the remove machine.
If the user doesn't press the button, but focuses the VNC viewer and 
presses Ctrl-V, the viewer sends the clipboard to the remote machine and 
only then sends the Ctrl-V to the remote machine.

In both cases, mouse or keyboard, you wouldn't need any more actions in 
practice. You still do Ctrl-C in your Linux app, switch to the viewer, 
press Ctrl-V there, and you got the text in notepad.exe.

Of course that would be configurable so that you can change they key 
combo, e.g. for Macs, or to disable sending the key combo after the 
Paste button, or to disable the clipboard entirely.


Dan Yefimov,

the RFB specification from 2007 happens to be linked from the page I 
mentioned, and funny enough... copypaste / clipboard isn't mentioned 
with a single word either.

Now, obviously, it is possible somehow, because it's working, so there 
is some way, but it was never part of the protocol.
And it cannot be claimed that every user somehow naturally knows how 
exactly it works and he realizes what it implies concretely for his work.

Ben

___
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/


Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread GloW - XD
fuckoff you ragdoll... i dont troll, and many on this fucking list
knows it... fuckit... i aint paying shit to anyone on this list, enjoy
finding your 0days, and, the next admins, go ahead and rm me, coz i
will be dropping your ass of a FD , until it makes me.
go die, and, maybe, you wont have money, and then, maybe, you will
have 10 wives, with 10 kids,.
now go eat a burger.
rat


On 25 January 2012 21:38, Christian Sciberras uuf6...@gmail.com wrote:
 No, I only read the manual.

 Now go troll somwhere else. :)

 On Wed, Jan 25, 2012 at 11:35 AM, GloW - XD doo...@gmail.com wrote:

 Windows is even more secure, have you actually, read any of the code /


 On 25 January 2012 21:30, Christian Sciberras uuf6...@gmail.com wrote:
  That's not necessarily true. On windows you can add custom
  clipboard formats
  that would contain a 'link' to the original source, causing the data
  to be
  actually
  passed when pasting. An example of this is when one copy+pastes a file.
  See the Windows Clipboard API for more info.
 
  Chris.
 
 
 
  On Wed, Jan 25, 2012 at 10:54 AM, Mario Vilas mvi...@gmail.com wrote:
 
  I'm not sure how the clipboard works in Linux desktops (I understand
  it's a little different), but at least in Windows environments data
  has to be copied to the clipboard when you hit Ctrl-C. It can't be
  copied when you hit Ctrl-V because then the applications wouldn't know
  if there is anything to paste (like you said, the button would be
  grayed).
 
  So to replicate this behavior it's necessary to send the data as it's
  copied, not as it's pasted. Most (not all, but most) desktop systems
  assume clipboard data can be freely shared with all applications and
  don't have any kind of isolation at all. VNC was designed with the
  same idea.
 
  The bottom line is, the problem here is using VNC for what Ben is
  using it. There are many more problems with that scenario and
  clipboard sharing may be the least of them.
 
  On Wed, Jan 25, 2012 at 8:44 AM, Peter Osterberg j...@vel.nu wrote:
   On 01/24/2012 07:18 PM, Mario Vilas wrote:
   Guys, could you please read carefully everything before you reply?
   I read carefully. It still didn't make sense, though.
  
   And you wouldn't be allowed to use copypaste while you edit
   sensitive
   documents either, I guess?
   I don't know how you could get to such a conclusion from what I
   wrote.
  
   You're reporting that if you copy and paste sensitive information
   and
   connect to a VNC session your clipboard data gets sent to the remote
   machine. That's pretty obvious and not a security hole that needs to
   be plugged.
  
   I don't think that is what Ben is saying. The clipboard get sent to
   the
   the server even before it is pasted, this happens without the user
   knowing of it.
  
   Notepad would have the paste button grayed otherwise, if the
   clipboard
   is empty, right? So it is already on the server before paste is
   pressed.
  
   So what ever was in the clipboard buffer is transmitted to the server
   on
   connection.
  
   This is at least the assumption I make from reading Ben's mails.
   Or...
   Is there a cliboard flag saying there is something on the clipboard,
   but
   it isn't transmitted until the user actually pastes? I haven't really
   got any experience with how the clipboard feature is implemented. My
   assumption is however that it has to be on server for notepad to be
   aware that Paste shouldn't be grayed out...
  
   I think Ben's report make complete sense actually, it would be better
   to
   have the clipboard feature as a default. Security before features...
   =)
  
   ___
   Full-Disclosure - We believe in it.
   Charter: http://lists.grok.org.uk/full-disclosure-charter.html
   Hosted and sponsored by Secunia - http://secunia.com/
 
 
 
  --
  “There's a reason we separate military and the police: one fights the
  enemy of the state, the other serves and protects the people. When the
  military becomes both, then the enemies of the state tend to become
  the people.”
 
  ___
  Full-Disclosure - We believe in it.
  Charter: http://lists.grok.org.uk/full-disclosure-charter.html
  Hosted and sponsored by Secunia - http://secunia.com/
 
 
 
  ___
  Full-Disclosure - We believe in it.
  Charter: http://lists.grok.org.uk/full-disclosure-charter.html
  Hosted and sponsored by Secunia - http://secunia.com/



___
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/


Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread GloW - XD
and stupidly, you forgot to addin the second PRIVT post i sent you,
saying i meant *insecure :)
now, go try tell me windows vnc is secure again...and, then setup a
vnc on your box, and, under win32, try your best, when your ready,
yell out, so i can make a compete fucking fool of ya.
ok ?
if this is how you want to play, i am challenging you, if i can own a
shitty windows setup you 'secure' as best you8 can, here on fd, is
this trolling is it ?
its a challenge... maybe, if you read the lame rfb and, pixelisation
via IP KVM, unfortunately for windows, it aint any different, a pixel
is placed at X or Y, and, you can place data calls to it, from server
wich, could be, my bot :)
want more proof,...keep going with my challenge then.


On 25 January 2012 21:38, Christian Sciberras uuf6...@gmail.com wrote:
 No, I only read the manual.

 Now go troll somwhere else. :)

 On Wed, Jan 25, 2012 at 11:35 AM, GloW - XD doo...@gmail.com wrote:

 Windows is even more secure, have you actually, read any of the code /


 On 25 January 2012 21:30, Christian Sciberras uuf6...@gmail.com wrote:
  That's not necessarily true. On windows you can add custom
  clipboard formats
  that would contain a 'link' to the original source, causing the data
  to be
  actually
  passed when pasting. An example of this is when one copy+pastes a file.
  See the Windows Clipboard API for more info.
 
  Chris.
 
 
 
  On Wed, Jan 25, 2012 at 10:54 AM, Mario Vilas mvi...@gmail.com wrote:
 
  I'm not sure how the clipboard works in Linux desktops (I understand
  it's a little different), but at least in Windows environments data
  has to be copied to the clipboard when you hit Ctrl-C. It can't be
  copied when you hit Ctrl-V because then the applications wouldn't know
  if there is anything to paste (like you said, the button would be
  grayed).
 
  So to replicate this behavior it's necessary to send the data as it's
  copied, not as it's pasted. Most (not all, but most) desktop systems
  assume clipboard data can be freely shared with all applications and
  don't have any kind of isolation at all. VNC was designed with the
  same idea.
 
  The bottom line is, the problem here is using VNC for what Ben is
  using it. There are many more problems with that scenario and
  clipboard sharing may be the least of them.
 
  On Wed, Jan 25, 2012 at 8:44 AM, Peter Osterberg j...@vel.nu wrote:
   On 01/24/2012 07:18 PM, Mario Vilas wrote:
   Guys, could you please read carefully everything before you reply?
   I read carefully. It still didn't make sense, though.
  
   And you wouldn't be allowed to use copypaste while you edit
   sensitive
   documents either, I guess?
   I don't know how you could get to such a conclusion from what I
   wrote.
  
   You're reporting that if you copy and paste sensitive information
   and
   connect to a VNC session your clipboard data gets sent to the remote
   machine. That's pretty obvious and not a security hole that needs to
   be plugged.
  
   I don't think that is what Ben is saying. The clipboard get sent to
   the
   the server even before it is pasted, this happens without the user
   knowing of it.
  
   Notepad would have the paste button grayed otherwise, if the
   clipboard
   is empty, right? So it is already on the server before paste is
   pressed.
  
   So what ever was in the clipboard buffer is transmitted to the server
   on
   connection.
  
   This is at least the assumption I make from reading Ben's mails.
   Or...
   Is there a cliboard flag saying there is something on the clipboard,
   but
   it isn't transmitted until the user actually pastes? I haven't really
   got any experience with how the clipboard feature is implemented. My
   assumption is however that it has to be on server for notepad to be
   aware that Paste shouldn't be grayed out...
  
   I think Ben's report make complete sense actually, it would be better
   to
   have the clipboard feature as a default. Security before features...
   =)
  
   ___
   Full-Disclosure - We believe in it.
   Charter: http://lists.grok.org.uk/full-disclosure-charter.html
   Hosted and sponsored by Secunia - http://secunia.com/
 
 
 
  --
  “There's a reason we separate military and the police: one fights the
  enemy of the state, the other serves and protects the people. When the
  military becomes both, then the enemies of the state tend to become
  the people.”
 
  ___
  Full-Disclosure - We believe in it.
  Charter: http://lists.grok.org.uk/full-disclosure-charter.html
  Hosted and sponsored by Secunia - http://secunia.com/
 
 
 
  ___
  Full-Disclosure - We believe in it.
  Charter: http://lists.grok.org.uk/full-disclosure-charter.html
  Hosted and sponsored by Secunia - http://secunia.com/



___
Full-Disclosure - We believe in it.
Charter: 

Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Christian Sciberras
For the record...
who are the other 'many on this list' that know you don't troll other than
your alter egos?
'course you don't troll can you quote me where I ever said VNC is
secure?

With that, I'll let you troll in peace. I have no interest talking to you
anyway... :)



On Wed, Jan 25, 2012 at 12:04 PM, GloW - XD doo...@gmail.com wrote:

 and stupidly, you forgot to addin the second PRIVT post i sent you,
 saying i meant *insecure :)
 now, go try tell me windows vnc is secure again...and, then setup a
 vnc on your box, and, under win32, try your best, when your ready,
 yell out, so i can make a compete fucking fool of ya.
 ok ?
 if this is how you want to play, i am challenging you, if i can own a
 shitty windows setup you 'secure' as best you8 can, here on fd, is
 this trolling is it ?
 its a challenge... maybe, if you read the lame rfb and, pixelisation
 via IP KVM, unfortunately for windows, it aint any different, a pixel
 is placed at X or Y, and, you can place data calls to it, from server
 wich, could be, my bot :)
 want more proof,...keep going with my challenge then.


 On 25 January 2012 21:38, Christian Sciberras uuf6...@gmail.com wrote:
  No, I only read the manual.
 
  Now go troll somwhere else. :)
 
  On Wed, Jan 25, 2012 at 11:35 AM, GloW - XD doo...@gmail.com wrote:
 
  Windows is even more secure, have you actually, read any of the code /
 
 
  On 25 January 2012 21:30, Christian Sciberras uuf6...@gmail.com
 wrote:
   That's not necessarily true. On windows you can add custom
   clipboard formats
   that would contain a 'link' to the original source, causing the data
   to be
   actually
   passed when pasting. An example of this is when one copy+pastes a
 file.
   See the Windows Clipboard API for more info.
  
   Chris.
  
  
  
   On Wed, Jan 25, 2012 at 10:54 AM, Mario Vilas mvi...@gmail.com
 wrote:
  
   I'm not sure how the clipboard works in Linux desktops (I understand
   it's a little different), but at least in Windows environments data
   has to be copied to the clipboard when you hit Ctrl-C. It can't be
   copied when you hit Ctrl-V because then the applications wouldn't
 know
   if there is anything to paste (like you said, the button would be
   grayed).
  
   So to replicate this behavior it's necessary to send the data as it's
   copied, not as it's pasted. Most (not all, but most) desktop systems
   assume clipboard data can be freely shared with all applications and
   don't have any kind of isolation at all. VNC was designed with the
   same idea.
  
   The bottom line is, the problem here is using VNC for what Ben is
   using it. There are many more problems with that scenario and
   clipboard sharing may be the least of them.
  
   On Wed, Jan 25, 2012 at 8:44 AM, Peter Osterberg j...@vel.nu wrote:
On 01/24/2012 07:18 PM, Mario Vilas wrote:
Guys, could you please read carefully everything before you
 reply?
I read carefully. It still didn't make sense, though.
   
And you wouldn't be allowed to use copypaste while you edit
sensitive
documents either, I guess?
I don't know how you could get to such a conclusion from what I
wrote.
   
You're reporting that if you copy and paste sensitive information
and
connect to a VNC session your clipboard data gets sent to the
 remote
machine. That's pretty obvious and not a security hole that needs
 to
be plugged.
   
I don't think that is what Ben is saying. The clipboard get sent to
the
the server even before it is pasted, this happens without the user
knowing of it.
   
Notepad would have the paste button grayed otherwise, if the
clipboard
is empty, right? So it is already on the server before paste is
pressed.
   
So what ever was in the clipboard buffer is transmitted to the
 server
on
connection.
   
This is at least the assumption I make from reading Ben's mails.
Or...
Is there a cliboard flag saying there is something on the
 clipboard,
but
it isn't transmitted until the user actually pastes? I haven't
 really
got any experience with how the clipboard feature is implemented.
 My
assumption is however that it has to be on server for notepad to be
aware that Paste shouldn't be grayed out...
   
I think Ben's report make complete sense actually, it would be
 better
to
have the clipboard feature as a default. Security before
 features...
=)
   
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 the
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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread coderman
On Wed, Jan 25, 2012 at 2:55 AM, Ben Bucksch n...@bucksch.org wrote:
 Dear coderman,

 posting mails that were explicitly marked offlist on the public list is
 no-go.

you must be new around here... why not let everyone learn from your fail?

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Gage Bystrom
What was the offlist message he was referring to? Cause yeah, he sounds
pretty new here with that kind of message. People bring in outside
conversations all the time, especially if they feel it is relevant to the
topic at hand.

Speaking of the topic at hand: I agree with the crowd that says it is not
explicitly a security bug, but more like a lack of a good feature. It
should be off by default, and someone on the list already made a patch to
remove the clipboard which you shouldn't be using for sensitive information
while connected to untrustworthy computers anyways. The developers should
be notified that they need the feature to turn clipboard sharing off, but
if they don't choose a different vnc and be on your way.

I don't view it as a security bug because its policy bug. It's not
something where this problem exists ergo I can exploit it, its a problem
where if they do something stupid, I can take advantage of it, and oh hey
their client by default doesn't mitigate this.

And before someone yells at me for how I seperate software bugs and policy
bugs by pointing out something like a client side attack: I view such
things as a mix. Policy bug that they are falling for it, and software bug
for the actual exploit.

And really this is a good example of a situation where if you are worried
about this you have bigger problems. Why must you use vnc? Why is what
you're connecting to untrustworthy? What information is directly at risk if
the box you're connecting to is compromised? What information is indirectly
at risk? Does the box running suspicious programs have access to the
internet? Etc.

Once you start going down the list on things that should be done, the need
to worry about this kind of bug becomes less and less relevant. Meaning if
this kind of problem IS relevant then I would almost bet money that you are
doing other things really wrong and so an attacker or a bad app doesn't
need to use this because they got far more easier and more rewarding things
to try.
On Jan 25, 2012 9:45 AM, coderman coder...@gmail.com wrote:

 On Wed, Jan 25, 2012 at 2:55 AM, Ben Bucksch n...@bucksch.org wrote:
  Dear coderman,
 
  posting mails that were explicitly marked offlist on the public list is
  no-go.

 you must be new around here... why not let everyone learn from your fail?

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-25 Thread Carlos Pantelides
 Those who try to manage potentially malicious servers do so over IP KVM,
 in which the foreign server basically gets only inbound Keyboard and 
Mouse and outbound uncompressed pixels.

Feature or bug, vnc or ip kvm, the same behavior has a virtual box virtualized 
machine with shared clipboard. You can choose disabled, direction and 
bidirectional (by default)

Something to keep in mind, at least the beginners like me.

Just run in the guest and see your clipboard, sure there are more elegant ways 
of doing the same. (tested linux in linux with virtual box and linux in mac 
with vmware)

while true; do
  xsel -p
  echo
  xsel -s
  echo
  xsel -b
  echo
done




Carlos Pantelides



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[Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Ben Bucksch
Affected Products: GNOME Vinagre and many other VNC viewers

Reproduction:
1. On your trusted desktop (e.g. Linux), open a text editor
2. Type My password, select the text, and hit Ctrl-C
3. Open a Vinagre VNC connection to a remote host, e.g. running an 
untrusted Windows
4. On the remote Windows host, open notepad.exe
5. In notepad's menu bar, using the mouse, click on Edit|Paste

Actual result:
notepad.exe shows My password
Expected result:
Nothing.

Impact:
Because I use a different password for every service, I have to 
copypaste them
(on my trusted desktop).

However, the remote machine is not trusted. In some cases, it's owned by 
a different company, in other cases I use VNC and a different machine 
specifically because I don't trust the software and want it jailed. If 
the untrusted host can get to my passwords from my trusted desktop, 
that's a critical security hole, because my passwords leak, and they may 
well give full access to other machines, my bank account or other highly 
sensitive data.

Affected users:
Using VNC is common usage pattern also used by government agencies
handling highly sensible documents (on the trusted host desktop system)
while moving dangerous but necessary uses like Internet access, Windows 
system
and similar needs on physically different machines that are accessed via 
VNC.
The purpose is that the untrusted system has no way to get to the 
information
on the trusted desktop, but that assumption is violated here.

Even normal users will be at risk. Many copypaste passwords, or they 
copypaste snipplets of sensitive Word processing documents, e.g. 
business plans.

Solution:
Given that most users are unaware of this risk, although the danger may 
nevertheless be very real for them, it is necessary for the default 
configuration to be secure. They cannot be expected to actively change 
preferences or the software to protect themselves, because the problem 
isn't obvious in the first place.

   Possible solutions:
1) a pref, with default off and a clear warning about this problem, 
because many users will not be aware of it. A pref with default on or 
without a clear warning is *not* sufficient.
2) Better yet: A button on the toolbar Copy clipboard Text is copied 
from host desktop clipboard to remote machine clipboard only when that 
button is pressed.
3) A combination of 1) and 2)

Vendor response:
The maintainer of the application has been informed via bugzilla, but 
has refused to acknowledge it as security problem.
https://bugzilla.gnome.org/show_bug.cgi?id=668544

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Giles Coochey
On 2012-01-24 13:34, Ben Bucksch wrote:
 Affected Products: GNOME Vinagre and many other VNC viewers

 Reproduction:
 1. On your trusted desktop (e.g. Linux), open a text editor
 2. Type My password, select the text, and hit Ctrl-C
 3. Open a Vinagre VNC connection to a remote host, e.g. running an
 untrusted Windows
 4. On the remote Windows host, open notepad.exe
 5. In notepad's menu bar, using the mouse, click on Edit|Paste

 Actual result:
 notepad.exe shows My password
 Expected result:
 Nothing.

 Impact:
 Because I use a different password for every service, I have to
 copypaste them
 (on my trusted desktop).

 However, the remote machine is not trusted. In some cases, it's owned 
 by
 a different company, in other cases I use VNC and a different machine
 specifically because I don't trust the software and want it jailed. 
 If
 the untrusted host can get to my passwords from my trusted desktop,
 that's a critical security hole, because my passwords leak, and they 
 may
 well give full access to other machines, my bank account or other 
 highly
 sensitive data.

 Affected users:
 Using VNC is common usage pattern also used by government agencies
 handling highly sensible documents (on the trusted host desktop 
 system)
 while moving dangerous but necessary uses like Internet access, 
 Windows
 system
 and similar needs on physically different machines that are accessed 
 via
 VNC.
 The purpose is that the untrusted system has no way to get to the
 information
 on the trusted desktop, but that assumption is violated here.

 Even normal users will be at risk. Many copypaste passwords, or they
 copypaste snipplets of sensitive Word processing documents, e.g.
 business plans.

 Solution:
 Given that most users are unaware of this risk, although the danger 
 may
 nevertheless be very real for them, it is necessary for the default
 configuration to be secure. They cannot be expected to actively 
 change
 preferences or the software to protect themselves, because the 
 problem
 isn't obvious in the first place.

Possible solutions:
 1) a pref, with default off and a clear warning about this problem,
 because many users will not be aware of it. A pref with default on or
 without a clear warning is *not* sufficient.
 2) Better yet: A button on the toolbar Copy clipboard Text is 
 copied
 from host desktop clipboard to remote machine clipboard only when 
 that
 button is pressed.
 3) A combination of 1) and 2)


Many viewers, including RealVNC have the option to disable the shared 
clipboard. Check your preferences.

-- 
Message sent via my webmail account.

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Mario Vilas
On Tue, Jan 24, 2012 at 2:34 PM, Ben Bucksch n...@bucksch.org wrote:
 Actual result:
 notepad.exe shows My password
 Expected result:
 Nothing.

No.

Expected result is to have the clipboard text sent to the remote
machine, if you have your client configured to do so. In a really
security sensitive environment you wouldn't be using the clipboard for
passwords anyway. Or you would disable clipboard sharing. Or you
wouldn't use a cleartext protocol to begin with.

You might as well report that if the user copies the password to the
clipboard at any other point during the session it also gets sent to
the server. I don't see why this should be the concern of the
developers of any VNC client.

-- 
“There's a reason we separate military and the police: one fights the
enemy of the state, the other serves and protects the people. When the
military becomes both, then the enemies of the state tend to become
the people.”

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Mario Vilas
 Guys, could you please read carefully everything before you reply?

I read carefully. It still didn't make sense, though.

 And you wouldn't be allowed to use copypaste while you edit sensitive
 documents either, I guess?

I don't know how you could get to such a conclusion from what I wrote.

You're reporting that if you copy and paste sensitive information and
connect to a VNC session your clipboard data gets sent to the remote
machine. That's pretty obvious and not a security hole that needs to
be plugged.

On top of that, the attack scenario doesn't sound too good either. I
fail to see why would you need to copypaste a password to access an
untrusted machine and then worry that machine might get to see the
password to itself. Also,most VNC servers store the password in clear
text in the configuration, and the entire protocol is in plain text,
for crying out loud.

A scenario where this could be a problem is so bizarre I sincerely
can't blame the


-- 
“There's a reason we separate military and the police: one fights the
enemy of the state, the other serves and protects the people. When the
military becomes both, then the enemies of the state tend to become
the people.”

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Ben Bucksch
On 24.01.2012 16:32, Giles Coochey wrote:
 Many viewers, including RealVNC have the option to disable the shared
 clipboard. Check your preferences.

Indeed. But Vinagre doesn't.

Even then, that is not sufficient, as explained in length.

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Ben Bucksch
On 24.01.2012 18:07, Mario Vilas wrote:
 Expected result is to have the clipboard text sent to the remote
 machine, if you have your client configured to do so

But I haven't done so. That's the bug.

 security sensitive environment you wouldn't be using the clipboard for
 passwords anyway.

And you wouldn't be allowed to use copypaste while you edit sensitive 
documents either, I guess?

Guys, could you please read carefully everything before you reply?

Ben

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Ben Bucksch
On 24.01.2012 19:18, Mario Vilas wrote:
 You're reporting that if you copy and paste sensitive information and
 connect to a VNC session your clipboard data gets sent to the remote
 machine. That's pretty obvious

If I have a VNC window somewhere on my desktop (in my case a virtual 
desktop or minimized), and continue with my work, 3 hours later when I 
work on some document or use some webapp, I don't remember that I have 
VNC session open and no, it's not obvious at all that this other host 
can read the communication between my local apps.

 On top of that, the attack scenario doesn't sound too good either. I
 fail to see why would you need to copypaste a password to access an
 untrusted machine and then worry that machine might get to see the
 password to itself.

You misunderstood. The remote machine can see *any* clipboard entries, 
even if I do something entirely different in a completely different 
application. I am browsing or using SSH and paste my password there, 
because the FF password manager failed, or I'm in a word processor or 
email app and write some document, which is entirely unrelated to the 
VNC session. I haven't looked at the VNC host since hours (but I have it 
constantly open for tasks that I need to do with untrusted software in a 
jail).

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Giles Coochey

On 24/01/2012 16:06, Ben Bucksch wrote:

On 24.01.2012 16:32, Giles Coochey wrote:

Many viewers, including RealVNC have the option to disable the shared
clipboard. Check your preferences.

Indeed. But Vinagre doesn't.

Even then, that is not sufficient, as explained in length.

I'm afraid as others have pointed out that by putting something in the 
Clipboard any local application can access that data, that's the point 
of the clipboard, to transfer the data between applications.


Now your argument is that you use an application that passes that 
clipboard to a remote server. From the forum posts I have seen this is 
an often requested feature and not usually considered a bug. The bug is 
what you're using the clipboard for, as you could have phrased your post 
that the problem is that the clipboard uses a plain text storage 
mechanism which makes the clipboard unsuitable for secure storage.


In any case, while not an option, there is a trivial patch to disable 
clipboard sharing in Vinagre:


--- a/src/vncconnection.c
+++ b/src/vncconnection.c
@@ -1579,14 +1579,7 @@
 gboolean vnc_connection_client_cut_text(VncConnection *conn,
const void *data, size_t length)
 {
-   guint8 pad[3] = {0};
-
-   vnc_connection_buffered_write_u8(conn, 6);
-   vnc_connection_buffered_write(conn, pad, 3);
-   vnc_connection_buffered_write_u32(conn, length);
-   vnc_connection_buffered_write(conn, data, length);
-   vnc_connection_buffered_flush(conn);
-   return !vnc_connection_has_error(conn);
+   return TRUE;
 }







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Description: S/MIME Cryptographic Signature
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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Ben Bucksch
On 24.01.2012 20:08, Giles Coochey wrote:
 I have seen this is an often requested feature

Yes, I understand. It can be highly useful. That's why I proposed to 
make a Paste button in the main toolbar (probably with a keyboard 
shortcut, too). So, the user would have to press one more button / key 
(3 actions instead of 2) to for the information to travel to the remote 
host. Compared to the risk, I think that's an acceptable tradeoff.

Please tell me that you have never ever copied a password (or anything 
else highly sensitive) using the clipboard.

I guess what makes my case and the government agency case different is 
that for you and others, VNC is typically the primary focus, but here on 
my machine it's running all the time, I have several test machines with 
untrusted software running and connected *always*.

 --- a/src/vncconnection.c
 +++ b/src/vncconnection.c 

Thanks for the patch!

Giles +1

Ben

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Giles Coochey

On 24/01/2012 19:20, Ben Bucksch wrote:

On 24.01.2012 20:08, Giles Coochey wrote:

I have seen this is an often requested feature

Yes, I understand. It can be highly useful. That's why I proposed to
make a Paste button in the main toolbar (probably with a keyboard
shortcut, too). So, the user would have to press one more button / key
(3 actions instead of 2) to for the information to travel to the remote
host. Compared to the risk, I think that's an acceptable tradeoff.

Please tell me that you have never ever copied a password (or anything
else highly sensitive) using the clipboard.

I have done this, and I have understood the risks.


I guess what makes my case and the government agency case different is
that for you and others, VNC is typically the primary focus, but here on
my machine it's running all the time, I have several test machines with
untrusted software running and connected *always*.

In my personal experience there was a case (a CDE - credit card data 
environment) where clipboard segregation between remote and local 
systems was a requirement. It was in this case that Citrix was chosen 
over other compteting 'remote-application' products because of a feature 
it had to disable the seamless clipboard functionality.


I think it is the case on whether this is a security issue depends on 
whether the VNC viewer in question is a fit tool for what you're using 
it for. Otherwise others may say it's a feature and not a bug, or at 
least your bug is my feature. I would see if you could ask them to have 
it as an optional feature though.


I would confirm that patch functions first - I found it in a thread 
regarding errors connecting to Mac OS X servers, and from the patch 
information, it may only stop the clipboard from server to client and 
not vice versa, but having seen it, I would imagine that you can find 
all the clipboard functions in the source and pretty much comment out 
their code.





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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Nick FitzGerald
Ben Bucksch wrote:

 Even then, that is not sufficient, as explained in length.

No -- what you explained in length _and_ seem impervious to 
understanding, despite a couple of respondents explaining it quite 
clearly, is that you have chosen to perform ongoing sensitive work in 
an environment where doing so is, at best, represents a highly 
questionable security stance.

_Part_ of what contributes to that questionability is your choice to 
more-or-less continuously run an application that you should always 
have known leaks access to the clipboard of what you oddly choose to 
describe as a trusted desktop (odd, because you should know that 
exposing the host clipboard to the client is common -- in fact, 
probably the standard default -- functionality of VNC clients).

That your chosen/preferred/whatever VNC client does not allow you to 
turn off, or otherwise modify or monitor this functionality is not a 
security vulnerability or bug, as you seem intent on portraying it.  It 
may be an undesirable feature (or, more accurately, lack of a feature) 
but don't you have other VNC clients to choose from?  Must you use this 
particular VNC client?  If so and this method of working is so critical 
to you, should you not choose a different platform for your trusted 
desktop and run a more suitably configurable VNC client?  Or, if your 
sensitive work is really that sensitive, should you not invest in a 
second machine for remotely monitoring/interacting with the the 
untrusted, sandboxed applications you need to run, so that they really 
are securely separated (can we all say air gap?) from your more 
sensitive operations?  It would not have to be a very heavy-duty 
machine -- a very low-end netbook style machine, or possibly even a 
cheap tablet-style device may more than suffice...

...

Another part of that questionability is obvious to anyone with nous 
reading this list...



Regards,

Nick FitzGerald


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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Dan Kaminsky
Those who try to manage potentially malicious servers do so over IP KVM, in
which the foreign server basically gets only inbound Keyboard and Mouse and
outbound uncompressed pixels.

Anything more is untrusted, for a reason.

On Tue, Jan 24, 2012 at 5:50 PM, Nick FitzGerald
n...@virus-l.demon.co.ukwrote:

 Ben Bucksch wrote:

  Even then, that is not sufficient, as explained in length.

 No -- what you explained in length _and_ seem impervious to
 understanding, despite a couple of respondents explaining it quite
 clearly, is that you have chosen to perform ongoing sensitive work in
 an environment where doing so is, at best, represents a highly
 questionable security stance.

 _Part_ of what contributes to that questionability is your choice to
 more-or-less continuously run an application that you should always
 have known leaks access to the clipboard of what you oddly choose to
 describe as a trusted desktop (odd, because you should know that
 exposing the host clipboard to the client is common -- in fact,
 probably the standard default -- functionality of VNC clients).

 That your chosen/preferred/whatever VNC client does not allow you to
 turn off, or otherwise modify or monitor this functionality is not a
 security vulnerability or bug, as you seem intent on portraying it.  It
 may be an undesirable feature (or, more accurately, lack of a feature)
 but don't you have other VNC clients to choose from?  Must you use this
 particular VNC client?  If so and this method of working is so critical
 to you, should you not choose a different platform for your trusted
 desktop and run a more suitably configurable VNC client?  Or, if your
 sensitive work is really that sensitive, should you not invest in a
 second machine for remotely monitoring/interacting with the the
 untrusted, sandboxed applications you need to run, so that they really
 are securely separated (can we all say air gap?) from your more
 sensitive operations?  It would not have to be a very heavy-duty
 machine -- a very low-end netbook style machine, or possibly even a
 cheap tablet-style device may more than suffice...

 ...

 Another part of that questionability is obvious to anyone with nous
 reading this list...



 Regards,

 Nick FitzGerald


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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Ben Bucksch
On 25.01.2012 00:09, Dan Kaminsky wrote:
 IP KVM, in which the foreign server basically gets only inbound 
 Keyboard and Mouse and outbound uncompressed pixels.

That is *precisely* what VNC is: an open-source IP KVM.

And please don't turn this into you're stupid, because I've seen 
others with the same setup. As mentioned, I know of a government agency 
with highly competent IT staff who had a similar setup: normal and 
sensitive work is on the desktop/notebook and Internet access (which is 
considered insecure) is on a remote machine, with a viewer on the desktop.

To make it clear: I take offense in the copying being *automatic*. I 
have nothing against the clipboard feature, per se. But if something 
happens automatically, how am I supposed to know that it happens? The 
user should make a conscious choice. That thinking would also help him 
realize the risk. Secure by default.

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Henri Salo
On Wed, Jan 25, 2012 at 12:47:28AM +0100, Ben Bucksch wrote:
 On 25.01.2012 00:09, Dan Kaminsky wrote:
  IP KVM, in which the foreign server basically gets only inbound 
  Keyboard and Mouse and outbound uncompressed pixels.
 
 That is *precisely* what VNC is: an open-source IP KVM.

What the hell? Seriously..

http://en.wikipedia.org/wiki/VNC

- Henri

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread coderman
On Tue, Jan 24, 2012 at 3:47 PM, Ben Bucksch n...@bucksch.org wrote:
 ...
 That is *precisely* what VNC is: an open-source IP KVM.

*precisely* ??

you keep using that word.
i do not think it means what you think it means...

this thread is full of lulz; you newbs might want to check out
  http://wiki.qubes-os.org/trac/wiki/CopyPaste

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Ben Bucksch
On 25.01.2012 00:52, Henri Salo wrote:
 On Wed, Jan 25, 2012 at 12:47:28AM +0100, Ben Bucksch wrote:
 On 25.01.2012 00:09, Dan Kaminsky wrote:
 IP KVM, in which the foreign server basically gets only inbound
 Keyboard and Mouse and outbound uncompressed pixels.
 That is *precisely* what VNC is: an open-source IP KVM.
 What the hell? Seriously..

 http://en.wikipedia.org/wiki/VNC

hihi. Thanks.

It transmits the keyboard and mouse events from one computer to 
another, relaying the graphical screen updates back in the other 
direction, over a network.
The VNC protocol (RFB) is very simple, based on one graphic primitive 
from server to client ('Put a rectangle of pixel data at the specified 
X,Y position') and event messages from client to server.

Compare to above.

Now, the part where it defines that clipboard is also a standard part of 
VNC... oh, huch, it's not there! (Just a random note that Unicode is 
impossible, but not that clipboard is defined as part of the protocol at 
all.) Ah, I know... Surely, it must be on 
http://en.wikipedia.org/wiki/RFB_protocol... No, same thing there. 
Strange.

So much for the lulz...

Ben

P.S. I was just reporting bug. I hope at least some software finds a 
better solution. Have fun.

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread coderman
On Tue, Jan 24, 2012 at 6:45 PM, Ben Bucksch n...@bucksch.org wrote:
 ...
 The VNC protocol (RFB) is very simple, based on one graphic primitive
 from server to client ('Put a rectangle of pixel data at the specified
 X,Y position') and event messages from client to server.

what Dan was trying to point out to you was the vast difference in
attack surface between an IP KVM and the VNC protocol and
architecture.

IP KVM: keyboard, video, mouse interface to physical ports. dumb dumb dumb.

VNC: not so simple full of bugs year after year privileged service
running on host hooking into various OS facilities and exposing all
sorts of vulnerabilities between server and client. sma^H^H^H^H stupid
stupid stupid (from a security perspective)

if you believe these present *precisely* the same risk profile,
well... can i have some of what you're smoking?



On Tue, Jan 24, 2012 at 6:34 PM, Ben Bucksch n...@bucksch.org wrote:
 On 25.01.2012 02:05, coderman wrote:
 you keep using that word.
 i do not think it means what you think it means...

 Where else did I use that word?
 And what does it mean, in your understanding, that differs from my usage? I
 checked the dict and it seems fine.

let me spell it out: your precise equivalency between a KVM device and
a VNC service is neither accurate nor correct.

http://www.youtube.com/watch?v=OHVjs4aobqs

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Re: [Full-disclosure] VNC viewers: Clipboard of host automatically sent to remote machine

2012-01-24 Thread Valdis . Kletnieks
On Tue, 24 Jan 2012 21:31:46 PST, coderman said:

 IP KVM: keyboard, video, mouse interface to physical ports. dumb dumb dumb.

Amen to that, brother.  Not even pixel-level access here. It's all VGA analog
video signal re-digitized and sent over IP (yes, really).  And you *really*
don't want to know how modesetting a multisync monitor at the other end of an
IP-KVM works.  The details have been known to make grown men cry. ;)





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