Home / mailings [SECURITY] [DSA 6291-1] haproxy security update
Posted on 22 May 2026
Debian Security Advisory- -------------------------------------------------------------------------
Debian Security Advisory DSA-6291-1 security@debian.org
https://www.debian.org/security/ Salvatore Bonaccorso
May 22, 2026 https://www.debian.org/security/faq
- -------------------------------------------------------------------------
Package : haproxy
CVE ID : CVE-2026-33555
Martino Spagnuolo reported that the HTTP/3 parsing code in HAProxy, a
fast and reliable load balancing reverse proxy, does not properly
validate the received body size and the announced content-length header,
which may result in HTTP request smuggling.
For the stable distribution (trixie), this problem has been fixed in
version 3.0.11-1+deb13u3.
We recommend that you upgrade your haproxy packages.
For the detailed security status of haproxy please refer to its security
tracker page at:
https://security-tracker.debian.org/tracker/haproxy
Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://www.debian.org/security/
Mailing list: debian-security-announce@lists.debian.org
