Vulnerability · Published May 9, 2026 · Assigned by PostgreSQL
CVE-2026-6666PgBouncer crash in kill_pool_logins_server_error
Medium 5.9
In plain English
A medium-severity null pointer dereference in PgBouncer. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 31% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)5.9Medium
Exploit odds (30 days)0.4%top 69.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack tooling1Public PoC
Official description
A possible null pointer reference in PgBouncer before 1.25.2 could lead to a crash, if a server sends an error response without SQLSTATE field.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | pgbouncer | no fix listed | DEBIAN-CVE-2026-6666 |
| Debian:13 | pgbouncer | 1.24.1-1+deb13u2 | DEBIAN-CVE-2026-6666 |
| Debian:14 | pgbouncer | 1.25.2-1 | DEBIAN-CVE-2026-6666 |
| Ubuntu:22.04:LTS | pgbouncer | no fix listed | UBUNTU-CVE-2026-6666 |
| Ubuntu:24.04:LTS | pgbouncer | no fix listed | UBUNTU-CVE-2026-6666 |
| Ubuntu:25.10 | pgbouncer | no fix listed | UBUNTU-CVE-2026-6666 |
| Ubuntu:26.04:LTS | pgbouncer | no fix listed | UBUNTU-CVE-2026-6666 |
| Ubuntu:26.10 | pgbouncer | no fix listed | UBUNTU-CVE-2026-6666 |
Affected products (as reported)
Weakness: CWE-476 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H