CVE-2025-1866
CWE-119Published: March 3, 2025· Updated: Jun 17, 2026
Official 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.
Technical Analysis
CVE-2025-1866 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
From a weakness classification perspective (CWE-119): Buffer overflow vulnerabilities can lead to arbitrary code execution or denial of service by corrupting adjacent memory.
CVSS v3.1 Vector Breakdown
Exploit & PoC Resources
All References (1)
Quick Facts
Related CVEs (CWE-119)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2025-1866 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts