CVE-2025-11679

Out-of-bounds Read in libwebsockets PNG parsing

MEDIUM
5.9
CVSS Score
Published: October 20, 2025 at 01:58 PM UTC
Updated: October 8, 2026 at 10:10 PM UTC
1 product affected across 1 vendorLibwebsockets

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Severity
MEDIUM5.9
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

4.0 ≤ v ≤ 4.3.64.0 ≤ v ≤ 4.4.24.0

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.9MEDIUMNozomi
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-125

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