CVE-2026-55707

Name	CVE-2026-55707
Description	In OpenStack Neutron before 28.0.2, the subnetpool onboarding API does not verify ownership of the target subnets. An authenticated user can onboard subnets from another project's shared network into their own subnetpool, mutating the victim's subnet state and altering L3 routing and address scope behavior for victim routers.
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	DLA-4735-1, DSA-6444-1
Debian Bugs	1143170

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
neutron (PTS)	bullseye (security), bullseye	2:17.2.1-0+deb11u1	vulnerable
	bookworm	2:21.0.0-7	vulnerable
	bookworm (security)	2:21.0.0-7+deb12u1	fixed
	trixie	2:26.0.3-0+deb13u2	vulnerable
	trixie (security)	2:26.0.3-0+deb13u3	fixed
	forky, sid	2:28.0.1-2	fixed

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

Package	Type	Release	Fixed Version	Origin	Debian Bugs
neutron	source	bookworm	2:21.0.0-7+deb12u1	DLA-4735-1
neutron	source	trixie	2:26.0.3-0+deb13u3	DSA-6444-1
neutron	source	(unstable)	2:28.0.1-2		1143170

https://security.openstack.org/ossa/OSSA-2026-032.html
https://bugs.launchpad.net/neutron/+bug/2152113