CWE-674 – Uncontrolled Recursion

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Description

The product does not properly control the amount of recursion which takes place, consuming excessive resources, such as allocated memory or the program stack.

Modes of Introduction:

– Implementation

 

 

Related Weaknesses

CWE-691

 

Consequences

Availability: DoS: Resource Consumption (CPU), DoS: Resource Consumption (Memory)

Resources including CPU, memory, and stack memory could be rapidly consumed or exhausted, eventually leading to an exit or crash.

Confidentiality: Read Application Data

In some cases, an application’s interpreter might kill a process or thread that appears to be consuming too much resources, such as with PHP’s memory_limit setting. When the interpreter kills the process/thread, it might report an error containing detailed information such as the application’s installation path.

 

Potential Mitigations

Phase: Implementation

Effectiveness: Moderate

Description: 

Ensure an end condition will be reached under all logic conditions. The end condition may include testing against the depth of recursion and exiting with an error if the recursion goes too deep. The complexity of the end condition contributes to the effectiveness of this action.

Phase: Implementation

Effectiveness: Limited

Description: 

Increase the stack size.

Increasing the stack size might only be a temporary measure, since the stack typically is still not very large, and it might remain easy for attackers to cause an out-of-stack fault.

CVE References

  • CVE-2007-3409
    • Self-referencing pointers create infinite loop and resultant stack exhaustion.
  • CVE-2016-10707
    • Javascript application accidentally changes input in a way that prevents a recursive call from detecting an exit condition.
  • CVE-2016-3627
    • An attempt to recover a corrupted XML file infinite recursion protection counter was not always incremented missing the exit condition.
  • CVE-2019-15118
    • USB-audio driver’s descriptor code parsing allows unlimited recursion leading to stack exhaustion.