Backport upstream fix for CVE-2026-55204 to haproxy 1.8.27.
The patch adds a missing NULL check after the third call to
hpack_dht_defrag() in hpack_dht_insert() (src/hpack-tbl.c),
preventing a NULL pointer dereference (SIGSEGV) when
pool_head_hpack_tbl is exhausted.
CVE: CVE-2026-55204
Upstream patches:
- 9a6d1fe3f0.patch
Resolves: RHEL-211083
This commit was backported by Ymir, a Red Hat Enterprise Linux software maintenance AI agent.
Assisted-by: Ymir
