CVE-2026-29079

Lexbor is a web browser engine library. Prior to 2.7.0, a type‑confusion vulnerability exists in Lexbor’s HTML fragment parser. When ns = UNDEF, a comment is created using the “unknown element” constructor. The comment’s data are written into the element’s fields via an unsafe cast, corrupting the qualified_name field. That corrupted value is later used as a pointer and dereferenced near the zero page. This vulnerability is fixed in 2.7.0.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/lexbor/lexbor/security/advisories/GHSA-mrpr-v36q-2vp8	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:lexbor:lexbor:*:*:*:*:*:*:*:*

History

18 Mar 2026, 20:20

Type	Values Removed	Values Added
First Time		Lexbor lexbor Lexbor
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
References	~~() https://github.com/lexbor/lexbor/security/advisories/GHSA-mrpr-v36q-2vp8 -~~	() https://github.com/lexbor/lexbor/security/advisories/GHSA-mrpr-v36q-2vp8 - Vendor Advisory
CPE		cpe:2.3:a:lexbor:lexbor::::::::

13 Mar 2026, 19:54

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-13 19:54

Updated : 2026-03-18 20:20

NVD link : CVE-2026-29079

Mitre link : CVE-2026-29079

CVE.ORG link : CVE-2026-29079

JSON object : View

Products Affected

lexbor

lexbor

CWE

CWE-843

Access of Resource Using Incompatible Type ('Type Confusion')

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