CVE-2026-6478

Name	CVE-2026-6478
Description	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.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-4646-1, DSA-6269-1, DSA-6270-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
postgresql-15 (PTS)	bookworm	15.18-0+deb12u1	fixed
	bookworm (security)	15.19-0+deb12u1	fixed
postgresql-17 (PTS)	trixie (security), trixie	17.11-0+deb13u1	fixed
postgresql-18 (PTS)	forky, sid	18.6-3	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Origin
postgresql-13	source	bullseye	13.23-0+deb11u4	DLA-4646-1
postgresql-13	source	(unstable)	(unfixed)
postgresql-15	source	bookworm	15.18-0+deb12u1	DSA-6269-1
postgresql-15	source	(unstable)	(unfixed)
postgresql-17	source	trixie	17.10-0+deb13u1	DSA-6270-1
postgresql-17	source	(unstable)	(unfixed)
postgresql-18	source	(unstable)	18.4-1

https://www.postgresql.org/about/news/postgresql-184-1710-1614-1518-and-1423-released-3297/