CVE-2026-56131

NameCVE-2026-56131
Descriptionlibexpat 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).
SourceCVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
ReferencesDLA-4765-1, DSA-6404-1
Debian Bugs1140387

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
expat (PTS)bookworm2.5.0-1+deb12u2vulnerable
bookworm (security)2.5.0-1+deb12u3fixed
trixie2.7.1-2vulnerable
trixie (security)2.8.3-1~deb13u1fixed
forky, sid2.8.4-1fixed

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
expatsourcebookworm2.5.0-1+deb12u3DLA-4765-1
expatsourcetrixie2.8.2-1~deb13u1DSA-6404-1
expatsource(unstable)2.8.2-11140387

Notes

https://github.com/libexpat/libexpat/pull/1267
Search for package or bug name: Reporting problems