CVE-2020-12689 - Improper Privilege Management vulnerability in Openstack Keystone

047910
CVSS 6.5 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
SINGLE
Confidentiality impact
PARTIAL
Integrity impact
PARTIAL
Availability impact
PARTIAL

Summary

An issue was discovered in OpenStack Keystone before 15.0.1, and 16.0.0. Any user authenticated within a limited scope (trust/oauth/application credential) can create an EC2 credential with an escalated permission, such as obtaining admin while the user is on a limited viewer role. This potentially allows a malicious user to act as the admin on a project another user has the admin role on, which can effectively grant that user global admin privileges.

Vulnerable Configurations

Common Weakness Enumeration (CWE)

CWE-269 - Improper Privilege Management

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Restful Privilege Elevation
    Rest uses standard HTTP (Get, Put, Delete) style permissions methods, but these are not necessarily correlated generally with back end programs. Strict interpretation of HTTP get methods means that these HTTP Get services should not be used to delete information on the server, but there is no access control mechanism to back up this logic. This means that unless the services are properly ACL'd and the application's service implementation are following these guidelines then an HTTP request can easily execute a delete or update on the server side. The attacker identifies a HTTP Get URL such as http://victimsite/updateOrder, which calls out to a program to update orders on a database or other resource. The URL is not idempotent so the request can be submitted multiple times by the attacker, additionally, the attacker may be able to exploit the URL published as a Get method that actually performs updates (instead of merely retrieving data). This may result in malicious or inadvertent altering of data on the server.