Rule: -- Sid: 2105 -- Summary: This event is generated when a remote user uses the IMAP AUTHENTICATE command to send a suspiciously long string to port 143 on an internal server. This may indicate an attempt to exploit a buffer overflow vulnerability in the IMAP AUTHENTICATE command. -- Impact: Serious. Possible remote execution of arbitrary code, which may lead to a remote root compromise. -- Detailed Information: When a large amount of data is sent to a vulnerable IMAP server in the AUTHENTICATE command, a buffer overflow condition may occur. This can allow the attacker to execute arbitrary code, which may allow the attacker to gain root access to the compromised server. -- Affected Systems: Any operating system that runs University of Washington imapd version 10.234 and earlier. -- Attack Scenarios: An attacker can send a sufficiently long AUTHENTICATE command to the IMAP server, creating a buffer overflow condition. This can then allow the attacker to gain root access to the compromised server. -- Ease of Attack: Simple. Exploits exist. -- False Positives: None known. -- False Negatives: None known. -- Corrective Action: Apply the appropriate patches for your operating system. Check the host for signs of compromise. -- Contributors: Sourcefire Research Team Brian Caswell <bmc@sourcefire.com> Sourcefire Technical Publications Team Jen Harvey <jennifer.harvey@sourcefire.com> -- Additional References: Bugtraq http://www.securityfocus.com/bid/130 CVE http://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=CVE-1999-0005 Nessus http://cgi.nessus.org/plugins/dump.php3?id=11073 --
