CVE-2025-11679

Out-of-bounds Read in libwebsockets PNG parsing

State: Published
Severity: 5.9 Medium
Published: Oct 20, 2025
Updated: Oct 20, 2025
Reserved: Oct 13, 2025

Description

Out-of-bounds Read in lws_upng_emit_next_line in warmcat libwebsockets allows, when the LWS_WITH_UPNG flag is enabled during compilation and the HTML display stack is used, to read past a heap allocated buffer possibly causing a crash, when the user visits an attacker controlled website that contains a crafted PNG file with a big height dimension.

Scores

CVSS	Score	Vector	Source
4.0	5.9 Medium	CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N	Nozomi

Weaknesses

CWE-125 Out-of-bounds Read

Affected Products

Product	Versions
libwebsocketswarmcat	4.0 through 4.4.2Affected 4.0 through 4.3.6Affected

References

https://libwebsockets.org/git/libwebsockets/commit?id=7df24cca7144d7bc9233b6b0a71108bd154ce101patchvendor-advisory
https://www.nozominetworks.com/labs/vulnerability-advisories-cve-2025-11679third-party-advisory

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.