Rule: -- Sid: 344 -- Summary: This event is generated when an attempt is made to exploit a vulnerability in Wu-ftpd. -- Impact: Serious. Full system compromise is possible. -- Detailed Information: Some versions of Wu-ftpd contain an exploitable vulnerability in SITE EXEC command, which can trigger a buffer overflow enabling an attacker to gain root privileges. Anonymous access is enough for this exploit to work. -- Affected Systems: Any version of Linux running wu-ftpd 2.6.0 and lower -- Attack Scenarios: An attacker tries to connect to the server on port 21 anonymously. Then he creates special directories using the MKD (make directory) command, and then change its current FTP path into them using the CWD (change current directory) command followed by a SITE EXEC on that directory. -- Ease of Attack: Simple. Exploit scripts are available. -- False Positives: None known. -- False Negatives: None known. -- Corrective Action: Disable anonymous FTP access to your site. Apply the appropriate vendor supplied patches. Upgrade to the latest non-affected version of the software. -- Contributors: Original Rule Writer Unknown Snort documentation contributed by Nawapong Nakjang (tony@ksc.net, tonie@thai.com) Sourcefire Research Team Nigel Houghton -- Additional References: CERT: http://www.cert.org/advisories/CA-2000-13.html --