Auth bypass in Openstack Keystone
CVE-2026-33551
An issue was discovered in OpenStack Keystone 14 through 26 before 26.1.1, 27.0.0, 28.0.0, and 29.0.0. Restricted application credentials can create EC2 credentials. By using a restricted application credential to call the EC2 credential creation API, an authenticated user with only a reader role may obtain an EC2/S3 credential that carries the full set of the parent user's S3 permissions, effectively bypassing the role restrictions imposed on the application credential. Only deployments that use restricted application credentials in combination with the EC2/S3 compatibility API (swift3 / s3api) are affected.
Vulnerability class: Broken Access Control
EPSS: 0.002 (12.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 3.5 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:N.
Affected products
- Openstack Keystone — versions 14.0.0, 27.0.0, 28.0.0
Weakness classification (CWE)
References
- cve@mitre.org (Exploit, Issue Tracking)
- cve@mitre.org (Patch, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Patch, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-33551?
- CVE-2026-33551 is a low-severity vulnerability in Openstack Keystone, classified under Incorrect Authorization. CVSS score: 3.5/10. Published 2026-04-10.
- How severe is CVE-2026-33551?
- Low severity. CVSS v3 base score is 3.5 out of 10.