Keystone /v3/credentials Unvalidated project_id Enables EC2 Token Cross-Project Lateral Movement
CVE-2026-43001 Published on May 1, 2026
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 Analysis
CVE-2026-43001 can be exploited with network access, and requires user privileges. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.
Weakness Types
What is an AuthZ Vulnerability?
The software performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.
CVE-2026-43001 has been classified to as an AuthZ vulnerability or weakness.
Improper Validation of Consistency within Input
The product receives a complex input with multiple elements or fields that must be consistent with each other, but it does not validate or incorrectly validates that the input is actually consistent.
Products Associated with CVE-2026-43001
You can be notified by email with stack.watch whenever vulnerabilities like CVE-2026-43001 are published in these products:
Affected Versions
OpenStack Keystone:- Version 14.0.0 and below 27.0.2 is affected.
- Version 28.0.0 and below 28.0.2 is affected.
- Version 29.0.0 and below 29.0.2 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.