libexpat UA Free prior to 2.8.4 via custom encode callback
CVE-2026-76957 Published on August 20, 2026

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.

NVD

Vulnerability Analysis

CVE-2026-76957 can be exploited with local system access, and does not require authorization privileges or user interaction. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to be low. considered to have a small impact on confidentiality and integrity and availability.

Attack Vector:
LOCAL
Attack Complexity:
HIGH
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
LOW
Integrity Impact:
LOW
Availability Impact:
LOW

Weakness Type

What is a Dangling pointer Vulnerability?

Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.

CVE-2026-76957 has been classified to as a Dangling pointer vulnerability or weakness.


Products Associated with CVE-2026-76957

stack.watch emails you whenever new vulnerabilities are published in Libexpatproject Libexpat or Canonical Ubuntu Linux. Just hit a watch button to start following.

 
 

Affected Versions

libexpat project libexpat: