High severity · published Aug 5, 2026
CVE-2026-55707
In OpenStack Neutron before 28.0.2, the subnetpool onboarding API does not verify ownership of the target subnets
7.1
CVSS
0.4%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 37% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NE
Neutron · OpenStack
14.0.0 before 26.0.6; 27.0.0 before 27.0.4; 28.0.0 before 28.0.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-55707
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-55707
launchpad.net
https://launchpad.net/bugs/2152113
security.openstack.org
https://security.openstack.org/ossa/OSSA-2026-032.html
www.openwall.com
https://www.openwall.com/lists/oss-security/2026/07/29/5
www.openwall.com
http://www.openwall.com/lists/oss-security/2026/07/29/5
lists.debian.org
https://lists.debian.org/debian-lts-announce/2026/08/msg00024.html
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