Summary
It was discovered that HAProxy incorrectly handled the FCGI demultiplexer
record length field. A remote attacker could possibly use this issue to
cause incorrect request routing, response smuggling, or other memory safety
issues. (CVE-2026-55203)
It was discovered that HAProxy failed to validate the return value of the
HPACK dynamic table defragmentation function when memory was exhausted. A
remote attacker could possibly use this issue to cause HAProxy to crash,
resulting in a denial of service. (CVE-2026-55204)
Fixed packages 4
| Release | Package | Fixed in |
|---|---|---|
| Ubuntu · 22.04 LTS 22.04:LTS | haproxy | 2.4.30-0ubuntu0.22.04.2 |
| Ubuntu · 24.04 LTS 24.04:LTS | haproxy | 2.8.16-0ubuntu0.24.04.3 |
| Ubuntu · 25.10 | haproxy | 3.0.12-0ubuntu0.25.10.5 |
| Ubuntu · 26.04 LTS 26.04:LTS | haproxy | 3.2.9-1ubuntu2.2 |