CVE-2026-6667: PgBouncer missing authorization for KILL_CLIENT admin command

CVE-2026-6667 · Severity: medium · CVSS 4.3 · Published 2026-05-09

PgBouncer, a popular connection pooler for PostgreSQL databases, contains a security flaw where the 'KILL_CLIENT' administrative command does not properly verify user permissions. This allows any user who has basic access to the administration console to forcibly disconnect other database clients, potentially causing service disruptions. While an attacker must already have authorized access to the admin console to exploit this, they could interfere with legitimate database operations and availability.

Technologies: PostgreSQL PgBouncer. Vendors: PostgreSQL.

Quick answers

Is CVE-2026-6667 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-6667 being exploited in the wild.
How severe is CVE-2026-6667?
Medium severity, with a CVSS score of 4.3, published 9 May 2026.
Which products and versions are affected?
PostgreSQL PgBouncer before 1.25.2.
Is there a fix for CVE-2026-6667?
A patch was published on 2026-05-08: Fixed in PgBouncer version 1.25.2 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-6667 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-6667?
Check whether you run PostgreSQL PgBouncer at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A missing authorization check (CWE-862) exists in PgBouncer's administration console regarding the 'KILL_CLIENT' command. While access to the administration console itself requires authentication, the software failed to restrict the 'KILL_CLIENT' command specifically to users defined in the 'admin_users' configuration parameter. Consequently, any authenticated user with access to the console (including those only intended to have read-only 'stats_users' access) can execute this command to terminate active client connections. This results in a partial loss of availability. The issue is resolved in version 1.25.2 by enforcing that only 'admin_users' can execute the command.

Affected products

  • PostgreSQL PgBouncer before 1.25.2

Timeline

  • 2026-05-08: patched: Fixed in PgBouncer version 1.25.2
  • 2026-05-09: disclosed: CVE-2026-6667 published

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.