CVE-2026-54291 pgjdbc CVE debrief

Who should care

Users of PostgreSQL JDBC driver versions 42.7.4 through 42.7.11 who rely on SCRAM-SHA-256-PLUS for authentication should be concerned about this vulnerability. An attacker could exploit this to intercept and manipulate data, potentially leading to unauthorized access or data breaches.

Technical summary

The pgjdbc vulnerability CVE-2026-54291 allows for a silent downgrade of the SCRAM-SHA-256-PLUS authentication mechanism to SCRAM-SHA-256, which lacks channel binding. This occurs because the com.ongres.scram:scram-client library returns an empty byte array instead of failing when encountering a server certificate with no tls-server-end-point channel-binding hash. As a result, an attacker can intercept the TLS connection and trigger the downgrade, bypassing the man-in-the-middle protection that SCRAM-SHA-256-PLUS is designed to provide. The vulnerability is addressed in pgjdbc version 42.7.12.

Defensive priority

High

Recommended defensive actions

• Upgrade to pgjdbc version 42.7.12 or later
• Use SCRAM-SHA-256-PLUS with channel binding for authentication
• Monitor for and block suspicious downgrade attempts
• Implement additional security measures such as TLS inspection and filtering
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE-2026-54291 vulnerability was publicly disclosed on 2026-07-06T19:17:08.407Z and last modified on 2026-07-09T13:16:25.717Z. The NVD entry is currently Analyzed. The vulnerability affects PostgreSQL JDBC driver versions 42.7.4 through 42.7.11.

Official resources