Two cooperating processes that simultaneously compete for a shared resource, in such a way that they violate the systems security policy, is commonly known as

A.
Covert channel

B.
Denial of Service

C.
Overt channel

D.
Object reuse

Explanation:
A: A covert channel or confi nement problem is an information flow issue. It is a communication channel allowing two cooperating processes to transfer information in such a way that it violates the systems security policy. There are two types of covert channels, viz. storage and timing. A covert storage channel involves the direct or indirect reading of a storage location by one process and a direct or indirect reading of the same storage location by another process. Typically, a covert storage channel involves a finite resource, such as a memory location or sector on a disk that is shared by two subjects at different security levels. This scenario is a description of a covert storage channel. A covert timing channel depends upon being able to influence the rate that some other process is able to acquire resources,
such as the CPU, memory, or I/O devices. Covert channels as opposed to what should be the case (overt channels) could lead to denial of service and object reuse has to do with disclosure protection when objects in memory are reused by different processes. Pages 175176.