CVE-2025-1866

Undefined Behavior Due to Out-of-Bounds Pointer Arithmetic in libwebsockets

State: Published
Severity: 10.0 Critical
Published: Mar 3, 2025
Updated: Mar 3, 2025
Reserved: Mar 3, 2025

Description

Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in warmcat libwebsockets allows Pointer Manipulation, potentially leading to out-of-bounds memory access. This issue affects libwebsockets before 4.3.4 and is present in code built specifically for the Win32 platform.

By default, the affected code is not executed unless one of the following conditions is met:

LWS_WITHOUT_EXTENSIONS (default ON) is manually set to OFF in CMake. LWS_WITH_HTTP_STREAM_COMPRESSION (default OFF) is manually set to ON in CMake. Despite these conditions, when triggered in affected configurations, this vulnerability may allow attackers to manipulate pointers, potentially leading to memory corruption or unexpected behavior.

Scores

CVSS	Score	Vector	Source
4.0	10.0 Critical	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H	GovTech CSG

Weaknesses

CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

Affected Products

Product	Versions
libwebsocketswarmcat	before <4.3.4Affectedfrom patch 4.3.4Not affected

References

https://github.com/warmcat/libwebsockets/commit/3f7c79fd57338aca1bf4a1b1f24e324b80d36265patch

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