Glossary

NULL pointer dereference

A program uses a pointer that is NULL as if it pointed to valid memory (CWE-476). It usually crashes the process, which is a denial of service, and in some kernels and embedded systems it can be exploitable.

Also called: null dereference
Defined in: MITRE CWE-476
Identifiers: CWE-476: NULL pointer dereference

Covered in

Guide

Find, fix and contain memory-safety bugs in C and C++

Recognize out-of-bounds access, use after free, NULL dereference and integer overflow in C and C++, fix them with checked lengths and single ownership, harden release builds, catch the rest with sanitizers and fuzzing, and plan new code in a memory-safe language.

Practice: Buffer over-read lab: Stop a heartbeat over-read