CVE-2009-3942: Martin Lambers Msmtp

Medium severity, CVSS 6.4. EPSS: 1.1% chance of exploitation in the next 30 days.

Martin Lambers msmtp before 1.4.19, when OpenSSL is used, does not properly handle a '\0' character in a domain name in the (1) subject's Common Name or (2) Subject Alternative Name 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

• Martin Lambers Msmtp: up to and including 1.4.18; version 0.2.5 only; version 0.2.6 only; version 0.3.0 only; version 0.3.1 only; version 0.4.0 only; …

Published 2009-11-16. Last modified 2026-06-16.