CVE - CVE-2025-43859

CVE-ID
CVE-2025-43859	Learn more at National Vulnerability Database (NVD) • CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
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.
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
MISC:https://github.com/python-hyper/h11/commit/114803a29ce50116dc47951c690ad4892b1a36ed URL:https://github.com/python-hyper/h11/commit/114803a29ce50116dc47951c690ad4892b1a36ed MISC:https://github.com/python-hyper/h11/security/advisories/GHSA-vqfr-h8mv-ghfj URL:https://github.com/python-hyper/h11/security/advisories/GHSA-vqfr-h8mv-ghfj
Assigning CNA
GitHub (maintainer security advisories)
Date Record Created
20250417	Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20250417)
Votes (Legacy)

Comments (Legacy)

Proposed (Legacy)
N/A
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