CVE-2026-74860

Name	CVE-2026-74860
Description	A flaw was found in libxml2 with Python bindings enabled. A remote attacker could exploit this vulnerability by providing a specially crafted XML document containing a Document Type Definition (DTD) with enumerated attribute values. This triggers a double-free error in the SAX attributeDecl callback handler, where a string is freed twice. This flaw can lead to a denial of service (DoS) due to a reproducible crash in Python applications using the libxml2 SAX bindings.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
libxml2 (PTS)	bookworm	2.9.14+dfsg-1.3~deb12u6	vulnerable
	bookworm (security)	2.9.14+dfsg-1.3~deb12u4	vulnerable
	trixie	2.12.7+dfsg+really2.9.14-2.1+deb13u3	vulnerable
	trixie (security)	2.12.7+dfsg+really2.9.14-2.1+deb13u1	vulnerable
	forky, sid	2.15.4+dfsg-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
libxml2	source	(unstable)	2.15.3+dfsg-1

Notes

https://bugzilla.redhat.com/show_bug.cgi?id=2529697
https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1076
https://gitlab.gnome.org/GNOME/libxml2/-/merge_requests/397
Fixed by: https://gitlab.gnome.org/GNOME/libxml2/-/commit/f41e1865781f74d1cadfe2fbdfeefed946026f12 (v2.15.3)