CVE-2026-6478: PostgreSQL

Medium severity, CVSS 6.5. EPSS: 0.6% chance of exploitation in the next 30 days.

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.

Affected products

• PostgreSQL PostgreSQL: before 14.23 (fixed in 14.23); from 15.0, before 15.18 (fixed in 15.18); from 16.0, before 16.14 (fixed in 16.14); from 17.0, before 17.10 (fixed in 17.10); from 18.0, before 18.4 (fixed in 18.4)

Published 2026-05-14. Last modified 2026-08-25.