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

17 Jun 2026, 10:29

Type	Values Removed	Values Added
Summary		(es) Lexbor es una biblioteca de motor de navegador web. Antes de la versión 2.7.0, existe una vulnerabilidad de confusión de tipos en el analizador de fragmentos HTML de Lexbor. Cuando ns = UNDEF, se crea un comentario utilizando el constructor de 'elemento desconocido'. Los datos del comentario se escriben en los campos del elemento a través de una conversión insegura, corrompiendo el campo qualified_name. Ese valor corrupto se utiliza posteriormente como puntero y se desreferencia cerca de la página cero. Esta vulnerabilidad se corrigió en la versión 2.7.0.

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 : 2026-06-17 10:29

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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