What is CVE-2026-6664?

CVE-2026-6664 is a high-severity vulnerability in Pgbouncer, classified under Integer Overflow or Wraparound. CVSS score: 7.5/10. Published 2026-05-09.

How severe is CVE-2026-6664?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2026-6664 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Integer overflow in Pgbouncer

CVE-2026-6664

An integer overflow in network packet parsing code in PgBouncer before 1.25.2 bypasses a boundary check and can lead to a crash. An unauthenticated remote attacker can crash PgBouncer with a malformed SCRAM authentication packet.

Vulnerability class: Integer Overflow

EPSS: 0.000 (15.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Pgbouncer
N/a Pgbouncer — versions 0

Weakness classification (CWE)

CWE-190 — Integer Overflow or Wraparound

Public proof-of-concept exploits

nicolasjulian/bouncer-overflow

References

f86ef6dc-4d3a-42ad-8f28-e6d5547a5007 (Release Notes)

Frequently asked questions

What is CVE-2026-6664?: CVE-2026-6664 is a high-severity vulnerability in Pgbouncer, classified under Integer Overflow or Wraparound. CVSS score: 7.5/10. Published 2026-05-09.
How severe is CVE-2026-6664?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2026-6664 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.