CVEvulnerability

CVE-2025-43859

9.1 CRITICAL Published 2025-04-24 Modified 2026-06-17 Official page ↗
Status
Deferred
Published
2025-04-24
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
9.1 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Weaknesses
CWE-444

Description

h11 is a Python implementation of HTTP/1.1. Prior to version 0.16.0, a leniency in h11's parsing of line terminators in chunked-coding message bodies can lead to request smuggling vulnerabilities under certain conditions. This issue has been patched in version 0.16.0. Since exploitation requires the combination of buggy h11 with a buggy (reverse) proxy, fixing either component is sufficient to mitigate this issue.

Related

Weakness · CWE (1)

  • CWE-444 Inconsistent Interpretation of HTTP Requests weakness

References