OpenStack Keystone has an Authorization Bypass

Overview

An issue was discovered in OpenStack Keystone before 29.0.2. The Keystone RBAC policy enforcer in enforce_call unconditionally merges the raw JSON request body into the policy enforcement dictionary via policy_dict.update(json_input.copy()), overwriting trusted target data that was previously set from database lookups. Because flask.request.get_json is called with force=True, this works regardless of Content-Type or HTTP method. Any authenticated user can inject arbitrary policy target attributes (e.g., user_id, project_id) into the request body to bypass RBAC checks and perform unauthorized operations on resources belonging to other users or projects. This was introduced in commit 5ea59f52 (Rocky/14.0.0).

Affected packages

• keystone >= 14.0.0, < 27.0.2
• keystone >= 28.0.0, < 28.0.2
• keystone >= 29.0.0, < 29.0.2

Remediation

Upgrade to a patched release:

• keystone 27.0.2
• keystone 28.0.2
• keystone 29.0.2