HAProxy through 3.4.0, fixed in commit 9a6d1fe, contains a null pointer dereference vulnerability in hpack_dht_insert() within src/hpack-tbl.c that fails to validate the return value of hpack_dht_defrag() when the memory pool is exhausted. An attacker can trigger HPACK dynamic table insertions under memory pressure to dereference a NULL pointer and crash HAProxy worker processes, causing denial of service.
Weakness
The product dereferences a pointer that it expects to be valid but is NULL.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Haproxy | Haproxy | * | 3.4.0 (including) |
| Red Hat Hardened Images | RedHat | haproxy-main-3.0.25-0.1.hum1 | * |
| Haproxy | Ubuntu | jammy | * |
| Haproxy | Ubuntu | noble | * |
| Haproxy | Ubuntu | questing | * |
| Haproxy | Ubuntu | resolute | * |