CVE-2026-76957

libexpat before 2.8.4 lacks handler call depth tracking with custom encoding callbacks. Thus, a use-after-free can occur. NOTE: this is similar to CVE-2026-50219, CVE-2026-56131 and CVE-2026-56412.

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/1322	Issue Tracking Patch Vendor Advisory
https://github.com/libexpat/libexpat/pull/1329	Issue Tracking Patch

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-08-20 05:16

Updated : 2026-09-08 20:56

NVD link : CVE-2026-76957

Mitre link : CVE-2026-76957

CVE.ORG link : CVE-2026-76957

JSON object : View

Products Affected

libexpat_project

libexpat

CWE

CWE-416

Use After Free

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