COMMON WEAKNESS ENUMERATIONDraft

CWE-252

Unchecked Return Value

The product does not check the return value from a method or function, which can prevent it from detecting unexpected states and conditions.

Soyutlama

Base

Yapı

Simple

Sömürü İhtimali

Low

Problemi anla

Problem nedir?

The product does not check the return value from a method or function, which can prevent it from detecting unexpected states and conditions.

Genişletilmiş açıklama

Two common programmer assumptions are "this function call can never fail" and "it doesn't matter if this function call fails". If an attacker can force the function to fail or otherwise return a value that is not expected, then the subsequent program logic could lead to a vulnerability, because the product is not in a state that the programmer assumes. For example, if the program calls a function to drop privileges but does not check the return code to ensure that privileges were successfully dropped, then the program will continue to operate with the higher privileges.

Kök neden

Problem nasıl ve ne zaman oluşur?

Yaşam döngüsü evresi

Implementation

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

Risk

Başarılı sömürü neye yol açar?

Unexpected StateDoS: Crash, Exit, or Restart

Etkilenen güvenlik alanları: Availability, Integrity

An unexpected return value could place the system in a state that could lead to a crash or other unintended behaviors.

Savunma

Nasıl önlenir ve çözülür?

Implementation

Uygulama aşaması savunması

Detay
Check the results of all functions that return a value and verify that the value is expected.

Etkinlik: High

Checking the return value of the function will typically be sufficient, however beware of race conditions (CWE-362) in a concurrent environment.

Implementation

Uygulama aşaması savunması

Detay
For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished [REF-1484].

Implementation

Uygulama aşaması savunması

Detay
Ensure that you account for all possible return values from the function.

Implementation

Uygulama aşaması savunması

Detay
When designing a function, make sure you return a value or throw an exception in case of an error.

Doğrulama

Nasıl tespit edilir?

Automated Static Analysis

High
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.)
CWE-252: Common Weakness Enumeration Entry CWE-252 · DayBreach Sözlük · DayBreach