Auth bypass in OpenStack Keystone
CVE-2026-44394
An issue was discovered in OpenStack Keystone before 29.0.2. The Keystone federated token rescoping mechanism does not propagate the original token's expiry to the newly issued token. When a federated user rescopes a token via POST /v3/auth/tokens, the handle_scoped_token() function in the mapped authentication plugin returns response data without an expires_at value. The token provider falls back to issuing a token with a fresh default TTL. By rescoping repeatedly before each token expires, a user can maintain access indefinitely, bypassing operator-configured token lifetime policies. This is a variant of CVE-2012-3426. Only deployments using federated identity (SAML2, OpenID Connect) are affected.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.0 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.003 (23.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 23.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- OpenStack Keystone — versions 14.0.0, 28.0.0, 29.0.0
Weakness classification (CWE)
References
- bugs.launchpad.net/keystone/+bug/2150379 (Exploit, Patch, Third Party Advisory, Issue Tracking)
- security.openstack.org/ossa/OSSA-2026-015.html (Patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-44394?
- CVE-2026-44394 is a medium-severity vulnerability in OpenStack Keystone, classified under Incorrect Authorization. CVSS score: 6.0/10. Published 2026-05-28.
- How severe is CVE-2026-44394?
- Medium severity. CVSS v3 base score is 6.0 out of 10.