CVE-2009-4028: MySQL

Medium severity, CVSS 6.8. EPSS: 1.8% chance of exploitation in the next 30 days.

The vio_verify_callback function in viosslfactories.c in MySQL 5.0.x before 5.0.88 and 5.1.x before 5.1.41, when OpenSSL is used, accepts a value of zero for the depth of X.509 certificates, which allows man-in-the-middle attackers to spoof arbitrary SSL-based MySQL servers via a crafted certificate, as demonstrated by a certificate presented by a server linked against the yaSSL library.

Affected products

• MySQL MySQL: up to and including 5.0.87; version 5.0.0 only; version 5.0.1 only; version 5.0.2 only; version 5.0.3 only; version 5.0.4 only; …
• Oracle MySQL: version 5.0.0 only; version 5.0.3 only; version 5.0.6 only; version 5.0.7 only; version 5.0.8 only; version 5.0.11 only; …

Published 2009-11-30. Last modified 2026-06-16.