CWE-476

NULL Pointer Dereference

High

Description

The product dereferences a pointer that it expects to be valid but is NULL.

Potential Impact

How to Fix

Implementation

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].

Requirements

Select a programming language that is not susceptible to these issues.

Implementation

Check the results of all functions that return a value and verify that the value is non-null before acting upon it.

Architecture and Design

Identify all variables and data stores that receive information from external sources, and apply input validation to make sure that they are only initialized to expected values.

Implementation

Explicitly initialize all variables and other data stores, either during declaration or just before the first usage.

Detection Methods

Related Weaknesses

References

View on MITRE CWE Database →

Need Help Fixing This Vulnerability?

Our security experts can help you identify and remediate CWE-476 vulnerabilities in your codebase.

Get Security Assessment