CVE-2026-9640

Name	CVE-2026-9640
Description	A privilege escalation vulnerability exists in LXD from 6.0 before 6.9, 5.21.0 before 5.21.5, and 5.0.0 before 5.0.7 regarding the handling of project-restriction policies during snapshot restoration.. An authenticated project operator in a restricted multi-tenant environment can bypass policy restrictions by importing a maliciously crafted instance backup containing restricted configuration keys within a snapshot. When the snapshot is restored, these restricted keys are applied to the live instance without policy validation. Starting the modified instance grants the operator unauthorized host root access.
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)
References	DSA-6373-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
lxd (PTS)	bookworm, bookworm (security)	5.0.2-5+deb12u6	vulnerable
	trixie	5.0.2+git20231211.1364ae4-9+deb13u6	vulnerable
	trixie (security)	5.0.2+git20231211.1364ae4-9+deb13u7	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
lxd	source	trixie	5.0.2+git20231211.1364ae4-9+deb13u7		DSA-6373-1
lxd	source	(unstable)	(unfixed)

Notes

https://github.com/canonical/lxd/security/advisories/GHSA-ppq7-4492-5552
https://github.com/canonical/lxd/pull/18301
https://github.com/canonical/lxd/pull/18303
https://github.com/canonical/lxd/pull/18304