CVE-2026-55204: NULL Pointer Dereference

HAProxy through 3.4.0, fixed in commit 9a6d1fe, contains a null pointer dereference vulnerability in hpackdhtinsert within src/hpack-tbl.c that fails to validate the return value of hpackdhtdefrag when the memory pool is exhausted. An attacker can trigger HPACK dynamic table insertions under memo...