This page tracks the Ubuntu fix status. The vulnerability itself is described on the main CVE page. View CVE-2026-6668 →

UBUNTU-CVE-2026-6668

Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an unauthenticated remote attacker to cause a denial of service....

Original description

The description as published by the source.

Integer overflow in the packet buffer growth logic in PgBouncer through 1.25.2 allows an unauthenticated remote attacker to cause a denial of service. Sufficiently large input makes the buffer size computation overflow, leaving the growth loop unable to terminate. Because PgBouncer serves all clients from a single process, this saturates a CPU core and stalls every pooled connection until the process is killed. Both unauthenticated and authenticated code paths can reach the overflow.

Source: OSV.dev (Open Source Vulnerabilities) OSV