Re: [Mimedefang] New spam technique

2004-07-05 Thread David F. Skoll
On Fri, 2 Jul 2004, Penelope Fudd wrote: Recently spammers verified their mailing list using this SMTP dialogue. This is an old technique called a dictionary attack or directory harvesting. Sendmail 8.13 has countermeasures, like closing a connection after N bad SMTP commands. I run a script

[Mimedefang] New spam technique

2004-07-05 Thread Penelope Fudd
Recently spammers verified their mailing list using this SMTP dialogue. How do I add this to mimedefang? 220 scotty.example.com ESMTP Sendmail 8.12.11/8.12.11; Thu, 1 Jul 2004 15:08:21 -0700 HELO c-24-1-219-157.client.comcast.net 250 scotty.example.com Hello c-24-1-219-157.client.comcast.net

Re: [Mimedefang] New spam technique

2004-07-05 Thread Les Mikesell
On Mon, 2004-07-05 at 09:50, David F. Skoll wrote: Recently spammers verified their mailing list using this SMTP dialogue. This is an old technique called a dictionary attack or directory harvesting. Sendmail 8.13 has countermeasures, like closing a connection after N bad SMTP commands.

Re: [Mimedefang] New spam technique

2004-07-05 Thread David F. Skoll
On Mon, 5 Jul 2004, Les Mikesell wrote: I think spammers have adapted by sending only a few addresses at a time, perhaps from virus-owned zombie relays. That was the logical next step. It's practically impossible to fight that. And honestly, until directory harvest attacks start overloading

[Mimedefang] Using Mail::GPG in filter to examine PGP attachments and message body

2004-07-05 Thread Paul Murphy
I'm trying to implement a corporate policy on use of encryption, with restrictions in the filter to enforce the policy as much as possible. The elements of the policy are: 1. All mail to selected domains must be encrypted 2. Encryption is to be all or nothing - if any unencrypted part is

RE: [Mimedefang] New spam technique

2004-07-05 Thread Paul Murphy
I think spammers have adapted by sending only a few addresses at a time, perhaps from virus-owned zombie relays. That was the logical next step. It's practically impossible to fight that. And honestly, until directory harvest attacks start overloading my machine or costing me

RE: [Mimedefang] New spam technique

2004-07-05 Thread David F. Skoll
On Mon, 5 Jul 2004, Paul Murphy wrote: One possible approach is to appear to accept all addresses, then check the recipient address but take no action until the DATA phase - at which point you can refuse the message with a 5xx error without indicating whether the address exists or not. That

[Mimedefang] block based on outgoing recipient

2004-07-05 Thread Lucas Albers
Would this item; in filter_end exclude all further mail filtering, on mail going from localhost to this a particular recipient? #in filter_end. if ($recipient =~ /[EMAIL PROTECTED]/) { exit; } Does not appear to be working... -- Luke Computer Science System Administrator Security

RE: [Mimedefang] Using Mail::GPG in filter to examine PGP attachments and messagebody

2004-07-05 Thread Richard Laager
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 $pass=PASS; my $gpg = Mail::GPG-new(default_key_id='4B771017', default_passphrase=$pass, debug=1, gnupg_hash_init={ armor = 1, batch = 1, homedir = '/home/defang'} ); Are you

[Mimedefang] file descriptor scope and embedded perl

2004-07-05 Thread Chris Masters
Hi All, Since upgrading to the latest MIMEDefang today I have bad file descriptor errors - I assume this is an embedded perl scope issue. So, I currently do the following: 1) I do *not* use filer_initialise 2) The file descriptor are global and are declared *outside* of any function. 3) valid

Re: [Mimedefang] ClamAV not detecting all viruses

2004-07-05 Thread Stewart James
Anyway, as of this posting, entity_contains_virus() functions are officially deprecated. They may be removed in a future version of MIMEDefang. thats funny - I thought message_contains_virus was depracated and entity_contains_virus was replacing it. That solves my problems pretty damn

Re: [Mimedefang] file descriptor scope and embedded perl

2004-07-05 Thread alan premselaar
Chris Masters wrote: Hi All, Since upgrading to the latest MIMEDefang today I have bad file descriptor errors - I assume this is an embedded perl scope issue. So, I currently do the following: 1) I do *not* use filer_initialise 2) The file descriptor are global and are declared *outside* of any

Re: [Mimedefang] block based on outgoing recipient

2004-07-05 Thread alan premselaar
Lucas Albers wrote: Would this item; in filter_end exclude all further mail filtering, on mail going from localhost to this a particular recipient? #in filter_end. if ($recipient =~ /[EMAIL PROTECTED]/) { exit; } Does not appear to be working... Lucas, if you just want to bypass all

Re: [Mimedefang] file descriptor scope and embedded perl

2004-07-05 Thread David F. Skoll
On Mon, 5 Jul 2004, Chris Masters wrote: Since upgrading to the latest MIMEDefang today I have bad file descriptor errors - I assume this is an embedded perl scope issue. Possibly. 1) I do *not* use filer_initialise You should probably use it. Any files opened at global scope outside any