Pgbouncer: community verdicts

4 notable / known-exploited Pgbouncer CVEs the community has triaged.

ⓘ Not an exhaustive list: we focus on the findings that matter (exploited / notable). For every Pgbouncer CVE, see NVD ↗.

CVE-2026-6664HIGH 7.5Real · low riskEPSS 1%
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.
CVE-2026-6665HIGH 8.1Real · low riskEPSS 0%
The SCRAM code in PgBouncer before 1.25.2 did not check the return value of strlcat() correctly when building the contents of the SCRAM client-final-message. A malicious backend that sends a SCRAM server-final-message with a long nonce can trigger a stack overflow.
CVE-2026-6666MED 5.9EPSS 0%
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.
CVE-2026-6667MED 4.3EPSS 0%
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.