CVE-2026-116740

libcss through 0.9.2 contains a NULL pointer dereference vulnerability in mq_parse_media_query() that allows remote attackers to crash consumers by supplying media lists ending in a comma. Attackers can serve a stylesheet whose @media or @import media list has a trailing comma, causing NetSurf or other parsers to crash.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/netsurf-browser/libcss
https://github.com/netsurf-browser/libcss/blob/release/0.9.2/src/parse/mq.c#L984
https://github.com/netsurf-browser/libcss/commit/006ffc4096040da13690abc380e5f828ec08284d
https://hackmd.io/@haindpwn/libcss-media-list-null-deref
https://www.vulncheck.com/advisories/libcss-through-0.9.2-null-pointer-dereference-via-media-query-parser

Configurations

No configuration.

History

26 Oct 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-26 22:16

Updated : 2026-10-31 03:17

NVD link : CVE-2026-116740

Mitre link : CVE-2026-116740

CVE.ORG link : CVE-2026-116740

JSON object : View

Products Affected

No product.

CWE

CWE-476

NULL Pointer Dereference

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