CVE-2026-107348 — Integer overflow causes an infinite loop in message buffer growth in PgBouncer
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through 1.26.0 allows a remote attacker to cause a denial of service when max_packet_siz…
Published: 2026-10-14 · CVSS: 5.9 · CVSS 3.1
Integer overflow in the message buffer growth logic (mbuf_make_room) in PgBouncer 1.21.0 through 1.26.0 allows a remote attacker to cause a denial of service when max_packet_size is configured above 2147483648. A packet header declaring a length above 2^31 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 restarted. Since 1.23.0 the overflow is reachable before authentication with a five-byte packet header.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7