CVE-2026-55204
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.
- Affected products
- Haproxy, Linuxmint, Rocky Linux, Ubuntu
- Haproxy
- ≤ 3.4.0
- Fix
- Available
- CVSS 4.0
- 8.7 HIGH
- CVSS 3.1
- 7.5 HIGH
- EPSS
- 0.5% (39th percentile)
- Weakness
- CWE-476
- NVD status
- Analyzed
- Published
- 2026-06-18
CVE-2026-55204 at NVD
No indexed exploits for CVE-2026-55204 yet
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