Auth bypass in Pgbouncer

CVE-2026-6667

PgBouncer before 1.25.2 did not perform an appropriate authorization check for the KILL_CLIENT admin command. All users with access to the administration console (which itself requires authorization) could run this command. It would have been correct to allow only users listed in the admin_users parameter.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.003 (23.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 23.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-6667: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-6667?
CVE-2026-6667 is a medium-severity vulnerability in Pgbouncer, classified under Missing Authorization. CVSS score: 4.3/10. Published 2026-05-09.
How severe is CVE-2026-6667?
Medium severity. CVSS v3 base score is 4.3 out of 10.