CWE-771 Missing Reference to Active Allocated Resource

The product does not properly maintain a reference to a resource that has been allocated, which prevents the resource from being reclaimed.

• Availability: DoS: Resource Consumption (Memory), DoS: Resource Consumption (Other) — If an attacker can create the conditions that mistakenly release a reference to a resource, then the attacker could prevent the resource from being reclaimed, deplete the available resource pool, and prevent other processes or threads from accessing the same type of resource.

• [Operation, Architecture and Design] Use resource-limiting settings provided by the operating system or environment. For example, when managing system resources in POSIX, setrlimit() can be used to set limits for certain types of resources, and getrlimit() can determine how many resources are available. However, these functions are not available on all operating systems. When the current levels get close to the maximum that is defined for the application (see CWE-770), then limit the allocation of further resources to privileged users; alternately, begin releasing resources for less-privileged users. While this mitigation may protect the system from attack, it will not necessarily stop attackers from adversely impacting other users. Ensure that the application performs the appropriate error checks and error handling in case resources become unavailable (CWE-703).

• Automated Static Analysis: Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)