CVE-2026-56412

libexpat before 2.8.2 does not consider XML_TOK_DATA_CHARS in doCdataSection and thus lacks handler call depth tracking for various calls from within handlers in cases of a policy violation. Thus, a use-after-free can occur. NOTE: this issue exists because of an incomplete fix for CVE-2026-50219.

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/1278	Patch Issue Tracking

Configurations

Configuration 1 (hide)

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

History

25 Oct 2026, 23:10

Type	Values Removed	Values Added
Summary		(es) libexpat antes de la versión 2.8.2 no considera XML_TOK_DATA_CHARS en doCdataSection y, por lo tanto, carece de seguimiento de la profundidad de las llamadas a los gestores para varias llamadas desde dentro de los gestores en casos de una violación de política. Así, un uso después de liberación puede ocurrir. NOTA: este problema existe debido a una corrección incompleta para CVE-2026-50219.

Information

Published : 2026-06-21 17:16

Updated : 2026-10-25 23:10

NVD link : CVE-2026-56412

Mitre link : CVE-2026-56412

CVE.ORG link : CVE-2026-56412

JSON object : View

Products Affected

libexpat_project

libexpat

CWE

CWE-416

Use After Free

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