CVE-2026-56131

EUVD-2026-37976
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).
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
mitreCNA
4.9 MEDIUM
LOCAL
HIGH
NONE
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
libexpat_projectlibexpat
𝑥
< 2.8.2
CNA
Debian logo
Debian Releases
Debian Product
Codename
expat
bookworm
vulnerable
bookworm (security)
vulnerable
bullseye
vulnerable
bullseye (security)
vulnerable
forky
vulnerable
sid
vulnerable
trixie
vulnerable
Common Weakness Enumeration
Vulnerability Media Exposure
References
https://github.com/libexpat/libexpat/pull/1267