Http4s is a Scala interface for HTTP services. In versions from 1.0.0-M1 to before 1.0.0-M45 and before 0.23.31, http4s is vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer section. This vulnerability could enable attackers to bypass front-end servers security controls, launch targeted attacks against active users, and poison web caches. A pre-requisite for exploitation involves the web application being deployed behind a reverse-proxy that forwards trailer headers. This issue has been patched in versions 1.0.0-M45 and 0.23.31.
History

Thu, 25 Sep 2025 08:30:00 +0000

Type Values Removed Values Added
First Time appeared Http4s
Http4s http4s
Vendors & Products Http4s
Http4s http4s

Tue, 23 Sep 2025 20:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 23 Sep 2025 19:00:00 +0000

Type Values Removed Values Added
Description Http4s is a Scala interface for HTTP services. In versions from 1.0.0-M1 to before 1.0.0-M45 and before 0.23.31, http4s is vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer section. This vulnerability could enable attackers to bypass front-end servers security controls, launch targeted attacks against active users, and poison web caches. A pre-requisite for exploitation involves the web application being deployed behind a reverse-proxy that forwards trailer headers. This issue has been patched in versions 1.0.0-M45 and 0.23.31.
Title Http4s vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer section
Weaknesses CWE-444
References
Metrics cvssV4_0

{'score': 6.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2025-09-23T18:54:42.867Z

Updated: 2025-09-23T19:17:26.320Z

Reserved: 2025-09-22T14:34:03.470Z

Link: CVE-2025-59822

cve-icon Vulnrichment

Updated: 2025-09-23T19:15:06.063Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-09-23T19:15:42.303

Modified: 2025-09-24T18:11:24.520

Link: CVE-2025-59822

cve-icon Redhat

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