An adversary utilizes a resource leak on the target to deplete the quantity of the resource available to service legitimate requests. Resource leaks most often come in the form of memory leaks where memory is allocated but never released after it has served its purpose, however, theoretically, any other resource that can be reserved can be targeted if the target fails to release the reservation when the reserved resource block is no longer needed. In this attack, the adversary determines what activity results in leaked resources and then triggers that activity on the target. Since some leaks may be small, this may require a large number of requests by the adversary. However, this attack differs from a flooding attack in that the rate of requests is generally not significant. This is because the lost resources due to the leak accumulate until the target is reset, usually by restarting it. Thus, a resource-poor adversary who would be unable to flood the target can still utilize this attack. Resource depletion through leak differs from resource depletion through allocation in that, in the former, the adversary may not be able to control the size of each leaked allocation, but instead allows the leak to accumulate until it is large enough to affect the target's performance. When depleting resources through allocation, the allocated resource may eventually be released by the target so the attack relies on making sure that the allocation size itself is prohibitive of normal operations by the target.
Likelihood Of Attack
This table shows the views that this attack pattern belongs to and top level categories within that view.
The target must have a resource leak that the adversary can repeatedly trigger.
None: No specialized resources are required to execute this type of attack.
This table specifies different individual consequences associated with the attack pattern. The Scope identifies the security property that is violated, while the Impact describes the negative technical impact that arises if an adversary succeeds in their attack. The Likelihood provides information about how likely the specific consequence is expected to be seen relative to the other consequences in the list. For example, there may be high likelihood that a pattern will be used to achieve a certain impact, but a low likelihood that it will be exploited to achieve a different impact.
If possible, leverage coding language(s) that do not allow this weakness to occur (e.g., Java, Ruby, and Python all perform automatic garbage collection that releases memory for objects that have been deallocated).
Memory should always be allocated/freed using matching functions (e.g., malloc/free, new/delete, etc.)
Implement best practices with respect to memory management, including the freeing of all allocated resources at all exit points and ensuring consistency with how and where memory is freed in a function.
A Related Weakness relationship associates a weakness with this attack pattern. Each association implies a weakness that must exist for a given attack to be successful. If multiple weaknesses are associated with the attack pattern, then any of the weaknesses (but not necessarily all) may be present for the attack to be successful. Each related weakness is identified by a CWE identifier.