An authenticated user with read-only privileges can cause the mongod process to terminate abnormally by issuing a crafted aggregation command, resulting in denial of service for all connected clients until the process is restarted. The issue stems from an internal engine selection inconsistency triggered by a specific combination of aggregation options.
Weakness
The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.
Extended Description
While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, it can still lead to a denial of service. For example, if a server handles multiple simultaneous connections, and an assert() occurs in one single connection that causes all other connections to be dropped, this is a reachable assertion that leads to a denial of service.