CVE-2026-54291: PostgreSQL Jdbc Driver

Medium severity, CVSS 5.9. EPSS: 0.2% chance of exploitation in the next 30 days.

pgjdbc is an open source postgresql JDBC Driver. In releases 42.7.4 through 42.7.11, channelBinding=require connections can be silently downgraded from SCRAM-SHA-256-PLUS with channel binding to plain SCRAM-SHA-256 without it, losing the man-in-the-middle protection the setting is meant to guarantee. An attacker who can intercept the TLS connection can trigger the downgrade with a certificate whose signature algorithm has no tls-server-end-point channel-binding hash, because the bundled com.ongres.scram:scram-client returns an empty byte array instead of failing and pgJDBC ScramAuthenticator checks only that the server advertised a PLUS mechanism, without rejecting the empty binding or checking that the negotiated mechanism uses channel binding. This issue is fixed in version 42.7.12.

Affected products

• PostgreSQL PostgreSQL Jdbc Driver: from 42.7.4, before 42.7.12 (fixed in 42.7.12)

Published 2026-07-06. Last modified 2026-07-09.