CWE-476 is NULL Pointer Dereference. The flaw arises when The product dereferences a pointer that it expects to be valid but is NULL. The database currently holds 456 vulnerabilities mapped to CWE-476 and 1 of them are in the CISA Known Exploited Vulnerabilities catalog.
Analyzing data...
The product dereferences a pointer that it expects to be valid but is NULL.
| Impact | Scope | Explanation |
|---|---|---|
| DoS: Crash, Exit, or Restart | Availability | NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation. |
| Execute Unauthorized Code or Commands, Read Memory, Modify Memory | Integrity, Confidentiality | In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution. |
| Method | Approach | Effectiveness |
|---|---|---|
| Automated Dynamic Analysis | This weakness can be detected using dynamic tools and techniques that interact with the software using large test suites with many diverse inputs, such as fuzz testing (fuzzing), robustness testing, and fault injection. The software's operation may slow down, but it should not become unstable, crash, or generate incorrect results. | Moderate |
| Manual Dynamic Analysis | Identify error conditions that are not likely to occur during normal usage and trigger them. For example, run the program under low memory conditions, run with insufficient privileges or permissions, interrupt a transaction before it is completed, or disable connectivity to basic network services such as DNS. Monitor the software for any unexpected behavior. If you trigger an unhandled exception or similar error that was discovered and handled by the application's environment, it may still indicate unexpected conditions that were not handled by the application itself. | - |
| Automated Static Analysis | 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.) | High |
| Automated Dynamic Analysis | Use tools that are integrated during compilation to insert runtime error-checking mechanisms related to memory safety errors, such as AddressSanitizer (ASan) for C/C++ [REF-1518].Crafted inputs are necessary to reach the code containing the error, such as generated by fuzzers. Also, these tools may reduce performance, and they only report the error condition - not the original mistake that led to the error. | Moderate |
Below are representative vulnerabilities related to this CWE, prioritized by severity.
CWE™ Program, operated by The MITRE Corporation. Copyright © 2006–2026, The MITRE Corporation. The MITRE Corporation hereby grants you a non-exclusive, royalty-free license to use CWE for research, development, and commercial purposes. CWE Terms of Use.
CyStack VulnScan continuously discovers assets, validates vulnerabilities, and helps security teams prioritize remediation across the organization.
Review CyStack's security rating and practical recommendations for websites and edge assets.
Explore cybersecurity research from our team of security specialists.
Browse practical cybersecurity knowledge across CyStack's articles and guides.
en
