Description
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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
n/a PgBouncer
Default version status: unaffected
1.21.0 to < 1.26.1affected