CVE-2006-6761: Novell NetMail IMAPD SUBSCRIBE stack buffer overflow

Automated analysis

Generated by VULONE's analysis model from the NVD record, CISA KEV and EPSS data on 20 September 2026. Confidence: medium.

high priorityRemote code execution in a mail server is severe, and the high EPSS score plus an exploit-tagged reference raise the likelihood of attempted exploitation despite the authentication requirement.

What it is

Novell NetMail's IMAP daemon (IMAPD) before 3.52e FTF2 contains a stack-based buffer overflow triggered by a long argument to the IMAP SUBSCRIBE command. A remote party who can authenticate to the IMAP service can overflow the stack and potentially execute arbitrary code in the daemon's context.

Impact

An authenticated remote attacker can corrupt the stack and potentially execute arbitrary code with the privileges of the IMAPD process, leading to full compromise of the mail server.

Attack surface

Reached over the network through the IMAP service by sending a crafted SUBSCRIBE command; the CVSS vector (AV:N/AC:L/Au:S) indicates authentication is required and no user interaction is needed.

Exploitation

Not listed in CISA KEV and no ransomware associations are recorded; EPSS is high (0.53112, 98.9th percentile) and one Secunia reference carries an Exploit tag, but no public exploit code is confirmed in the record.

What to do

• Upgrade Novell NetMail to 3.52e FTF2 or later, which the vendor references as the fixed release.
• Restrict IMAP access to trusted networks and require strong authentication to limit who can reach the SUBSCRIBE command.
• Monitor IMAP logs for malformed or oversized SUBSCRIBE arguments and alert on repeated failures.
• If NetMail is end-of-life or unsupported, migrate to a maintained mail platform or isolate the service behind a filtering proxy.

Detection

• Inspect IMAP server logs for SUBSCRIBE commands with unusually long mailbox arguments.
• Deploy network IDS/IPS signatures for oversized SUBSCRIBE requests to the IMAP port.
• Monitor the IMAPD process for crashes, restarts, or unexpected child processes that could indicate exploitation.

This assessment is produced automatically and is not human-reviewed. Verify against the vendor advisory before acting on it.