SNMP Community String [7:31373]

2002-01-09 Thread Kwame

Is there a way to encrypt the snmp community strings?  The strings are
security holes since there are tools out there (I know of at least one)
capable of deriving the RW strings, given the RO strings. Once the RW
strings are known, you can download the config files and hack the passwords
although I'm yet to see enable secret passwords cracked (I could be wrong).




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Re: SNMP Community String [7:31373]

2002-01-09 Thread Raul F. Fernandez-IGLOU

Just access-list it.
- Original Message -
From: Kwame 
To: 
Sent: Wednesday, January 09, 2002 8:03 AM
Subject: SNMP Community String [7:31373]


 Is there a way to encrypt the snmp community strings?  The strings are
 security holes since there are tools out there (I know of at least one)
 capable of deriving the RW strings, given the RO strings. Once the RW
 strings are known, you can download the config files and hack the
passwords
 although I'm yet to see enable secret passwords cracked (I could be
wrong).




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7i=31376t=31373
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RE: SNMP Community String [7:31373]

2002-01-09 Thread Andrew Larkins

Not to sure about that, but you can add access lists to control who is
allowed to use those SNMP strings

snmp-server community abcd rw 50
access-list 50 permit 1.2.3.4 0.0.0.255

-Original Message-
From: Kwame [mailto:[EMAIL PROTECTED]]
Sent: 09 January 2002 15:04 PM
To: [EMAIL PROTECTED]
Subject: SNMP Community String [7:31373]


Is there a way to encrypt the snmp community strings?  The strings are
security holes since there are tools out there (I know of at least one)
capable of deriving the RW strings, given the RO strings. Once the RW
strings are known, you can download the config files and hack the passwords
although I'm yet to see enable secret passwords cracked (I could be wrong).




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7i=31378t=31373
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RE: SNMP Community String [7:31373]

2002-01-09 Thread Andras Bellak

Try using snmpv3

-Original Message-
From: Andrew Larkins [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, January 09, 2002 5:53 AM
To: [EMAIL PROTECTED]
Subject: RE: SNMP Community String [7:31373]


Not to sure about that, but you can add access lists to control who is
allowed to use those SNMP strings

snmp-server community abcd rw 50
access-list 50 permit 1.2.3.4 0.0.0.255

-Original Message-
From: Kwame [mailto:[EMAIL PROTECTED]]
Sent: 09 January 2002 15:04 PM
To: [EMAIL PROTECTED]
Subject: SNMP Community String [7:31373]


Is there a way to encrypt the snmp community strings?  The strings are
security holes since there are tools out there (I know of at least one)
capable of deriving the RW strings, given the RO strings. Once the RW
strings are known, you can download the config files and hack the
passwords
although I'm yet to see enable secret passwords cracked (I could be
wrong).




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7i=31392t=31373
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RE: SNMP Community String [7:31373]

2002-01-09 Thread Dion, Thierry

SNMPv3-Version 3 of the Simple Network Management Protocol. 
SNMPv3 is an interoperable standards-based protocol defined in RFCs
2273-2275. 
SNMPv3 provides secure access to devices by a combination of authenticating
and encrypting packets over the network.

The security features provided in SNMPv3 are:

Message integrity-Ensuring that a packet has not been tampered with
in-transit.
Authentication-Determining the message is from a valid source.
Encryption-Scrambling the contents of a packet prevent it from being
seen by an unauthorized source.

Cisco Source



-Message d'origine-
De : Andras Bellak [mailto:[EMAIL PROTECTED]]
Envoyi : mercredi 9 janvier 2002 15:38
@ : [EMAIL PROTECTED]
Objet : RE: SNMP Community String [7:31373]


Try using snmpv3

-Original Message-
From: Andrew Larkins [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, January 09, 2002 5:53 AM
To: [EMAIL PROTECTED]
Subject: RE: SNMP Community String [7:31373]


Not to sure about that, but you can add access lists to control who is
allowed to use those SNMP strings

snmp-server community abcd rw 50
access-list 50 permit 1.2.3.4 0.0.0.255

-Original Message-
From: Kwame [mailto:[EMAIL PROTECTED]]
Sent: 09 January 2002 15:04 PM
To: [EMAIL PROTECTED]
Subject: SNMP Community String [7:31373]


Is there a way to encrypt the snmp community strings?  The strings are
security holes since there are tools out there (I know of at least one)
capable of deriving the RW strings, given the RO strings. Once the RW
strings are known, you can download the config files and hack the
passwords
although I'm yet to see enable secret passwords cracked (I could be
wrong).




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7i=31399t=31373
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Re: SNMP Community String [7:31373]

2002-01-09 Thread David Tran

First of all, your SNMP string can be encrypted with DES.  I think it
can be encrypted in MD5 as well, even though I have not personally
seen it; however, I have encrypted SNMP string in DES myself.  Cisco
TACACS freeware does come with a generate_passwd utility that will
allow you to encrypt a text string into DES.  I use this utility on
Linux/BSD
platform and it works great.  If you want to encrypt your string in MD5,
I suggest that you do that on a Linux machine.  If you have root privilege,
you can create a user, assign that user a password that matches the string
of your choice.  After that, you can retrieve the MD5 hash string from the
/etc/shadow (only root can read this file).  This is a very simple task.

The next question you ask is that if the enable secret password, which
is an MD5 hash, can be cracked.  The answer is a resounding YES.
I use a program called John the Ripper (available on Unix platform)
to crack MD5 hash password.  Now granted that it takes longer to crack
MD5 password thatn DES or 3DES; however, if the MD5 password is
dictionary-based and/or less than 8 characters long, it takes less than a
day
to crack the password.  I've personally tested it on a dual-processor PIII
600MHz with 256MB of RAM.

Finally, how do you protect yourself?  Well, for SNMP, use version 3
because everything is encrypted (make sure your IOS supports it).
Make everyone who logs onto the router/switch authenticate via
TACACS.  Enable aaa authorization and aaa accounting on the
router/switch.  Having done all that, the only time that you will ever use
the enable secret password on the router is when your router loses
connectivity with the TACACS server.  Therefore, it will be useless
for anyone who happen to decode your enable secret password
anyway.  Last, if you really want to be secure, do not telnet to
the router, use Secure Shell (SSH) instead.  That way, your
router/switch will be protected from password sniffer and cracker.
Cisco only supports SSH version 1 which sucks big time but it is still
better than telnet.


- Original Message -
From: Kwame 
To: 
Sent: Wednesday, January 09, 2002 8:03 AM
Subject: SNMP Community String [7:31373]


 Is there a way to encrypt the snmp community strings?  The strings are
 security holes since there are tools out there (I know of at least one)
 capable of deriving the RW strings, given the RO strings. Once the RW
 strings are known, you can download the config files and hack the
passwords
 although I'm yet to see enable secret passwords cracked (I could be
wrong).




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7i=31497t=31373
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