CVE-2026-50219
expat: libexpat: Use-after-free vulnerability due to improper handler call depth tracking
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · June 4, 2026
Updated · November 1, 2026
Description
A flaw was found in libexpat. This vulnerability occurs because the library, in versions before 2.8.2, does not properly track handler call depth when certain XML parsing functions are invoked from within handlers during a policy violation. This oversight can lead to a use-after-free condition, which may result in information disclosure, integrity loss, or denial of service.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
CVSS / CWE
CVSS 3.1 · 4.9CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
CWE-911 · Improper Update of Reference Count