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CWE WEAKNESSES  /  CWE-253

CWE-253

Incorrect Check of Function Return Value

Base EXPLOIT LIKELIHOOD: LOW

What it is

The product incorrectly checks a return value from a function, which prevents it from detecting errors or exceptional conditions.

Important and common functions will return some value about the success of its actions. This will alert the program whether or not to handle any errors caused by that function.

Impact

Availability, IntegrityUnexpected State, DoS: Crash, Exit, or Restart

Mitigations

  • [Architecture and Design] Use a language or compiler that uses exceptions and requires the catching of those exceptions.
  • [Implementation] Properly check all functions which return a value.
  • [Implementation] When designing any function make sure you return a value or throw an exception in case of an error.

Real-world CVE examples

  • CVE-2023-49286 — Chain: function in web caching proxy does not correctly check a return value (CWE-253) leading to a reachable assertion (CWE-617)

Related weaknesses

Test & detect

Browse all common weaknesses, check related exploited CVEs, or map to ATT&CK techniques.

Source: MITRE CWE. View on cwe.mitre.org →

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