CVE-2026-56131

libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation. Thus, a use-after-free can occur (similar to the CVE-2026-50219 situation).

CVSS v3 4.9 MEDIUM

4.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.4 / Impact : 3.4

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/libexpat/libexpat/pull/1267	Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*

History

26 Oct 2026, 11:10

Type	Values Removed	Values Added
Summary		(es) libexpat antes de 2.8.2 carece de seguimiento de la profundidad de las llamadas del gestor para las llamadas a XML_ResumeParser desde dentro de los gestores en casos de una violación de política. Así, puede ocurrir un uso después de liberación (similar a la situación de CVE-2026-50219).

Information

Published : 2026-06-19 06:17

Updated : 2026-10-26 11:10

NVD link : CVE-2026-56131

Mitre link : CVE-2026-56131

CVE.ORG link : CVE-2026-56131

JSON object : View

Products Affected

libexpat_project

libexpat

CWE

CWE-416

Use After Free

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