CVE-2009-2666: Fetchmail

Medium severity, CVSS 6.4. EPSS: 1.5% chance of exploitation in the next 30 days.

socket.c in fetchmail before 6.3.11 does not properly handle a '\0' character in a domain name in the subject's Common Name (CN) field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.

Affected products

• Fetchmail Fetchmail: up to and including 6.3.10; version 4.5.1 only; version 4.5.2 only; version 4.5.3 only; version 4.5.4 only; version 4.5.5 only; …

Published 2009-08-07. Last modified 2026-06-16.