Uncontrolled Resource Consumption
Microsoft Exchange 2000 allows remote authenticated attackers to cause a denial of service via a large number of rapid requests, which consumes all of the licenses that are granted to Exchange by IIS.
CWE-400 - Uncontrolled resource consumption
An uncontrolled resource allocation attack (also known as resource exhaustion attack) triggers unauthorized overconsumption of the limited resources in an application, such as memory, file system storage, database connection pool entries, and CPU. This may lead to denial of service for valid users and degradation of the application's functionality as well as that of the host operating system.