WarehousePG (WHPG) 7.2.1 through 7.6.0 is affected by a missing authorization vulnerability (CWE-862) in the built-in function gp_log_backend_memory_contexts(). Any authenticated database role can run this function without a GRANT. It also gets around the superuser restriction that PostgreSQL places on the underlying pg_log_backend_memory_contexts() function. A low-privileged user can force the segment backends of any other session, superuser sessions included, to write their memory context details to the segment server logs, which the attacker cannot read. Those details can include query text from other users cached plans, and the call can be repeated to generate large amounts of log output. WarehousePG 6.x is not affected.
Weakness
The product does not perform an authorization check when an actor attempts to access a resource or perform an action.
Potential Mitigations
- Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) [REF-229] to enforce the roles at the appropriate boundaries.
- Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
- For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page.
- One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.