Re: New mail blocks result of Ralsky's latest attacks?

[Steven Champeon <schampeo () hesketh com>]

on Fri, Oct 10, 2003 at 08:47:51PM +0530, Suresh Ramasubramanian wrote:
> Set up header checks in sendmail / postfix to block all mail with 
> Received: headers showing Ralsky IPs.  PCRE header checks in postfix 
> would be like -

<snip>

Sendmail rulesets to block Ralsky:

KRalsky1 regex -a@SPAM ^.*(\[|\(|\s)211\.158\.[3456789]
KRalsky2 regex -a@SPAM ^.*(\[|\(|\s)218\.70\.1[345]
KRalsky3 regex -a@SPAM ^.*(\[|\(|\s)219\.153\.1[45]
KRalsky4 regex -a@SPAM ^.*(\[|\(|\s)218\.10\.57
KRalsky5 regex -a@SPAM ^.*(\[|\(|\s)218\.70\.1[01]
KRalsky6 regex -a@SPAM ^.*(\[|\(|\s)218\.70\.[89]

KReceivedChecks sequence Ralsky1 Ralsky2 Ralsky3 Ralsky4 Ralsky5 Ralsky6

HReceived: $>check_header_Received
Scheck_header_Received
R$*                     $: $1 $| $(ReceivedChecks $&{currHeader} $)
R$* $| @SPAM            $#error $@ 5.7.1 $: "550 Message rejected; suspected spam signature."
R$* $| $*               $: $1

This will not help to block direct SMTP AUTH attacks; but they should block
mail from other compromised servers, provided they don't munge the headers.
I've been running these rules for several weeks without incident.

HTH,
Steve

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