NULL Pointer Dereference Vulnerability in libcss Affects NetSurf and Other Parsers
CVE-2026-116740

7.1HIGH

Key Information:

Vendor

Netsurf-browser

Status
Libcss
Vendor
CVE Published:
26 October 2026

What is CVE-2026-116740?

A vulnerability in libcss versions up to 0.9.2 allows remote attackers to exploit a NULL pointer dereference issue within the mq_parse_media_query function. By providing a media list that ends with a comma, attackers can induce a crash in consumers like NetSurf or other compatible parsers. This could potentially disrupt service and make applications utilizing libcss vulnerable to denial of service attacks.

Affected Version(s)

libcss 0 <= 0.9.2

References

https://github.com/netsurf-browser/libcss/commit/006ffc40...
patch
https://github.com/netsurf-browser/libcss
product
https://github.com/netsurf-browser/libcss/blob/release/0....
technical-description

CVSS V4

Score:
7.1
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

HaiND from the Post and Telecommunication Institute of Technology
metan-ucw
.