Auth bypass in OpenStack Keystone
CVE-2026-43001
An issue was discovered in OpenStack Keystone before 29.0.2. POST /v3/credentials did not validate that the caller-supplied project_id for an EC2-type credential matched the project of the authenticating application credential. This allowed an attacker holding an unrestricted application credential for project A to create an EC2 credential targeting project B; a subsequent /v3/ec2tokens exchange would then issue a Keystone token scoped to project B while still carrying the original app_cred_id, enabling cross-project lateral movement within the credential owner's role footprint.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.9 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:L.
EPSS exploit prediction
EPSS: 0.006 (47.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 47.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.006 · change: +0.001
Affected products
- OpenStack Keystone — versions 14.0.0, 13, 28.0.0
Weakness classification (CWE)
References
- bugs.launchpad.net/keystone/+bug/2149775 (Exploit, Patch, Third Party Advisory, Issue Tracking)
- review.opendev.org/c/openstack/keystone/+/985804 (Patch)
- security.openstack.org/ossa/OSSA-2026-015.html (Patch, Vendor Advisory)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-43001?
- CVE-2026-43001 is a high-severity vulnerability in OpenStack Keystone, classified under Incorrect Authorization. CVSS score: 7.9/10. Published 2026-05-01.
- How severe is CVE-2026-43001?
- High severity. CVSS v3 base score is 7.9 out of 10.