Vulnerability · Published Jul 6, 2026 · Assigned by GitHub_M
CVE-2026-54291Silent channel-binding authentication downgrade via unsupported certificate algorithms
High 8.2
In plain English
A high-severity security flaw in pgjdbc from pgjdbc. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 15% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | libpgjava | no fix listed | DEBIAN-CVE-2026-54291 |
| Debian:13 | libpgjava | no fix listed | DEBIAN-CVE-2026-54291 |
| Debian:14 | libpgjava | 42.7.12-1 | DEBIAN-CVE-2026-54291 |
| Maven | org.postgresql:postgresql | 42.7.12 | GHSA-j92g-9f8w-j867 |
| Ubuntu:25.10 | libpgjava | no fix listed | UBUNTU-CVE-2026-54291 |
| Ubuntu:26.04:LTS | libpgjava | no fix listed | UBUNTU-CVE-2026-54291 |
| Ubuntu:26.10 | libpgjava | no fix listed | UBUNTU-CVE-2026-54291 |
Affected products (as reported)
Weakness: CWE-636, CWE-757 · Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:L/SA:N
References
- https://github.com/pgjdbc/pgjdbc/security/advisories/GHSA-j92g-9f8w-j867 x_refsource_CONFIRM
- https://github.com/pgjdbc/pgjdbc/commit/77df98e4e66c12936ded3478a0954f6f580bad99 x_refsource_MISC
- https://github.com/ongres/scram/releases/tag/3.3 x_refsource_MISC