CWE-1265

Mitigation

Phase: Architecture and Design

Description:

• When architecting a system that will execute untrusted code in response to events, consider executing the untrusted event handlers asynchronously (asynchronous message passing) as opposed to executing them synchronously at the time each event fires. The untrusted code should execute at the start of the next iteration of the thread's message loop. In this way, calls into non-reentrant code are strictly serialized, so that each operation completes fully before the next operation begins. Special attention must be paid to all places where type coercion may result in script execution. Performing all needed coercions at the very beginning of an operation can help reduce the chance of operations executing at unexpected junctures.

Mitigation

Phase: Implementation

Description:

• Make sure the code (e.g., function or class) in question is reentrant by not leveraging non-local data, not modifying its own code, and not calling other non-reentrant code.

CAPEC-74: Manipulating State

['The adversary modifies state information maintained by the target software or causes a state transition in hardware. If successful, the target will use this tainted state and execute in an unintended manner.', 'State management is an important function within a software application. User state maintained by the application can include usernames, payment information, browsing history as well as application-specific contents such as items in a shopping cart. Manipulating user state can be employed by an adversary to elevate privilege, conduct fraudulent transactions or otherwise modify the flow of the application to derive certain benefits.', 'If there is a hardware logic error in a finite state machine, the adversary can use this to put the system in an undefined state which could cause a denial of service or exposure of secure data.']