CVE-2026-6478

Covert timing channel in comparison of MD5-hashed password in PostgreSQL authentication allows an attacker to recover user credentials sufficient to authenticate.  This does not affect scram-sha-256 passwords, the default in all supported releases.  However, current databases may have MD5-hashed passwords originating in upgrades from PostgreSQL 13 or earlier.  Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.