Lexbor up to 2.6.x qualified_name type confusion

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Lexbor up to 2.6.x. Affected is an unknown function. Performing a manipulation of the argument qualified_name results in type confusion. This vulnerability is cataloged as CVE-2026-29079. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Lexbor up to 2.6.x. This affects an unknown functionality. The manipulation of the argument qualified_name with an unknown input leads to a type confusion vulnerability. CWE is classifying the issue as CWE-843. The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type. This is going to have an impact on availability. The summary by CVE is:

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.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-29079 since 03/03/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 313734 (Fedora 44 : php (2026-c66eaae759)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.7.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (313734) and EUVD (EUVD-2026-12054). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Type confusion
CWE: CWE-843
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 313734
Nessus Name: Fedora 44 : php (2026-c66eaae759)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Lexbor 2.7.0

Timelineinfo

03/03/2026 CVE reserved
03/13/2026 +10 days Advisory disclosed
03/13/2026 +0 days VulDB entry created
05/11/2026 +59 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-29079 (🔒)
GCVE (CVE): GCVE-0-2026-29079
GCVE (VulDB): GCVE-100-351009
EUVD: 🔒

Entryinfo

Created: 03/13/2026 20:20
Updated: 05/11/2026 10:56
Changes: 03/13/2026 20:20 (65), 03/13/2026 20:44 (1), 03/20/2026 05:49 (12), 05/11/2026 10:56 (2)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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