CVE-2026-56131 PUBLISHED

Assigner: mitre
Reserved: 19.06.2026 Published: 19.06.2026 Updated: 19.06.2026

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).

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
CVSS Score: 4.9

Attack Vector	Local	Scope	Unchanged
Attack Complexity	High	Confidentiality Impact	Low
Privileges Required	None	Integrity Impact	Low
User Interaction	None	Availability Impact	Low

CVSS 3.1

Product Status

Vendor	libexpat project
Product	libexpat
Versions	Default: unaffected affected from 0 to 2.8.2 (excl.)

References

https://github.com/libexpat/libexpat/pull/1267

Problem Types

CWE-416 Use After Free CWE