CVE-2025-11680

Out-of-bounds Write in libwebsockets PNG parsing

Published Oct 20, 2025 CVSS 4.0 · 5.9 Medium EPSS < 1% KEV · Not listed
Description
Out-of-bounds Write in unfilter_scanline in warmcat libwebsockets allows, when the LWS_WITH_UPNG flag is enabled during compilation and the HTML display stack is used, to write 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 width value that causes an integer overflow which value is used for determining the size of a heap allocation.

Remediation

Vendor Solution

Update the library to its latest stable release, if not possible backport the fix commit 2b715249f39291c86443b969a1088d59b6a89b78

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 3.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L'}

threat_severity

Low

Type Values Removed Values Added
First Time appeared Warmcat
Warmcat libwebsockets
Vendors & Products Warmcat
Warmcat libwebsockets
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Out-of-bounds Write in unfilter_scanline in warmcat libwebsockets allows, when the LWS_WITH_UPNG flag is enabled during compilation and the HTML display stack is used, to write 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 width value that causes an integer overflow which value is used for determining the size of a heap allocation.
Title Out-of-bounds Write in libwebsockets PNG parsing
Weaknesses CWE-787
References
Metrics cvssV4_0

{'score': 5.9, 'vector': '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Nozomi
Published
Updated
Oct 20, 2025, 2:34 PM
Reserved
Oct 13, 2025, 9:57 AM
Status
Deferred
Published
Oct 20, 2025, 2:15 PM
Modified
Oct 8, 2026, 10:10 PM
Severity
Low
Public date
Oct 20, 2025, 2:04 PM