CVE-2026-29079 HIGH

CVE-2026-29079: Type Confusion in Lexbor Fragment Parser

Vendor Lexbor
Product lexbor
Weakness CWE-843
Published March 13, 2026
Last update March 16, 2026

CVSS base score

8.2/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

March 13, 2026 CVE published
March 16, 2026 Record updated