Use After Free Affecting expat package, versions <2.5.0-1+deb12u3


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.18% (8th percentile)

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  • Snyk IDSNYK-ECHOLATEST-EXPAT-18426796
  • published30 Jul 2026
  • disclosed19 Jun 2026

Introduced: 19 Jun 2026

CVE-2026-56131  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Echo:latest expat to version 2.5.0-1+deb12u3 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream expat package and not the expat package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

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 Base Scores

version 3.1