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| Subject: | RE: Strange SMTP sessions with 'helo=<large negative number>' syntax |
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| Date: | Thu, 29 Dec 2005 14:39:00 -0800 |
Little-endian versus big-endian? There's no end to the possible bugs.... Dave
-----Original Message----- From: Michel Arboi [mailto:michel.arboi@gmail.com] Sent: Thursday, December 29, 2005 1:01 AM To: max Cc: incidents@securityfocus.com Subject: Re: Strange SMTP sessions with 'helo=<large negative number>' syntax On 28/12/05, max <max@neuropunks.org> wrote:to=<dylanfans-unsubscribe@dylanirvana.com> proto=SMTP helo=<-1217882552> Notice that helo section is a negative number (which is why my postfix rejects the message)Spammers sometimes hide IP addresses (in URL) by using a 32 bits integer. And also that they often use buggy tools.<grin> Maybe they tried to use this trick in the HELO command? -1217882552+2^32 = 3077084744 = 183.104.150.72 -1218008120+2^32 = 3076959176 = 183.102.171.200 Both addresses seems to be unassigned, my hypothesis looks wrong :-(Has anyone noticed this as well?I don't have this in my logs.
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