Security Incidents mailing list archives
Re: Proxy attackers/hijackers
From: Joe Stewart <jstewart () lurhq com>
Date: Fri, 17 Oct 2003 10:15:37 -0400
On Thursday 16 October 2003 11:31 pm, Jeff Kell wrote:
We had an attempted proxy rape today on a trojanned dorm machine. No mail escaped thanks to firewalling but I did track down the culprits and the compromised ports (which appear random, they changed when the machine was rebooted). Do not have the machine (yet) for forensics to see what infected it, but it was providing two proxy ports on random ports that change when the machine is rebooted (apparently, given the time difference between the pairs of proxy ports below).
If the two proxy ports start at a random port but themselves are sequential, it could be the Autoproxy trojan. A rash of these was installed yesterday by a second mass-hack of a large webhosting provider. Autoproxy can be detected when it attempts to make outbound HTTP control connections (one is to a CGI script where it reports its port numbers and stats, the other is to an uninvolved third-party website for connectivity checking). In these connections it sets its User-Agent header to "Autoproxy/0.2". The snort signature below will catch these connections leaving your network and let you know if you have any infected hosts. alert tcp $HOME_NET any -> $EXTERNAL_NET 80 (msg:"Autoproxy Trojan control connection"; flags:A+; content: "|0d 0a 55 73 65 72 2d 41 67 65 6e 74 3a 20 41 75 74 6f 70 72 6f 78 79 2f|"; reference:url,www.lurhq.com/autoproxy.html; classtype:trojan-activity; sid:1000028; rev:1;) -Joe -- Joe Stewart, GCIH Senior Security Researcher LURHQ http://www.lurhq.com/ --------------------------------------------------------------------------- FREE Whitepaper: Better Management for Network Security Looking for a better way to manage your IP security? Learn how Solsoft can help you: - Ensure robust IP security through policy-based management - Make firewall, VPN, and NAT rules interoperable across heterogeneous networks - Quickly respond to network events from a central console Download our FREE whitepaper at: http://www.securityfocus.com/sponsor/Solsoft_incidents_031015 ----------------------------------------------------------------------------
Current thread:
- Proxy attackers/hijackers Jeff Kell (Oct 17)
- Re: Proxy attackers/hijackers Joe Stewart (Oct 17)
- <Possible follow-ups>
- RE: Proxy attackers/hijackers Carey, Steve T GARRISON (Oct 17)
- Proxy attackers/hijackers Thomas Willner (Oct 20)
- Re: [Dshield] Proxy attackers/hijackers Thor Larholm (Oct 19)
- RE: Proxy attackers/hijackers James C. Slora, Jr. (Oct 20)