CVE-2026-111139

NetSurf libnsbmp through 0.1.7 contains an out-of-bounds read vulnerability in bmp_decode_mask() that allows attackers to read one byte past the image buffer by supplying crafted ICO files. Attackers can provide an ICO whose inner bitmap width is not a multiple of 8, causing a heap over-read that can crash applications calling bmp_decode().

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://download.netsurf-browser.org/libs/releases/libnsbmp-0.1.7-src.tar.gz
https://github.com/netsurf-browser/libnsbmp
https://github.com/netsurf-browser/libnsbmp/blob/ea063c9f46acb43e90208da14073332b505ef7e7/src/libnsbmp.c#L835-L873
https://hackmd.io/@haind-pwn/libnsbmp-rle-absolute-pad-and-ico-mask-oob-read
https://www.vulncheck.com/advisories/netsurf-libnsbmp-through-0.1.7-out-of-bounds-read-via-bmp-decode-mask

Configurations

No configuration.

History

15 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-15 19:17

Updated : 2026-10-26 15:16

NVD link : CVE-2026-111139

Mitre link : CVE-2026-111139

CVE.ORG link : CVE-2026-111139

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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