CVE-2026-29079: Lexbor

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

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.

Affected products

• Lexbor Lexbor: before 2.7.0 (fixed in 2.7.0)

Published 2026-03-13. Last modified 2026-06-17.