GHSA-5mp8-rq5m-pj7mMediumCVSS 4.0
An issue was discovered in HAProxy before 3.3.6. The HTTP/3 parser does not check that the...
🔗 CVE IDs covered (1)
📋 Description
An issue was discovered in HAProxy before 3.3.6. The HTTP/3 parser does not check that the received body length matches a previously announced content-length when the stream is closed via a frame with an empty payload. This can cause desynchronization issues with the backend server and could be used for request smuggling. The earliest affected version is 2.6.
🔗 References (8)
- https://nvd.nist.gov/vuln/detail/CVE-2026-33555
- https://github.com/haproxy/haproxy/commit/05a295441c621089ffa4318daf0dbca2dd756a84
- https://www.haproxy.com/documentation/haproxy-aloha/changelog
- https://www.haproxy.org
- https://www.mail-archive.com/[email protected]/msg46752.html
- https://r3verii.github.io/cve/2026/04/14/haproxy-h3-standalone-fin-smuggling.html
- https://lists.debian.org/debian-lts-announce/2026/10/msg00036.html
- https://github.com/advisories/GHSA-5mp8-rq5m-pj7m