Integer Overflow Vulnerability in PgBouncer by PgBouncer Team

CVE-2026-6668

What is CVE-2026-6668?

An integer overflow in PgBouncer's packet buffer growth logic can be exploited by an unauthenticated remote attacker to initiate a denial of service condition. When excessively large input is provided, the buffer size calculation overflows, causing the buffer growth loop to stall. Since PgBouncer operates all client connections from a single process, this issue can overwhelm a CPU core, leading to the stalling of all pooled connections. Affected instances will continue to face connectivity issues until the process is forcibly terminated, impacting both unauthenticated and authenticated paths.

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