What is the authoritative source for CWE-825?

Expired Pointer Dereference (CWE-825) is catalogued in MITRE CWE and curated for EU compliance use cases by SQUR.

BaseIncomplete

CWE-825Expired Pointer Dereference

Category: memory

Description

The product dereferences a pointer that contains a location for memory that was previously valid, but is no longer valid. When a product releases memory, but it maintains a pointer to that memory, then the memory might be re-allocated at a later time. If the original pointer is accessed to read or write data, then this could cause the product to read or modify data that is in use by a different function or process. Depending on how the newly-allocated memory is used, this could lead to a denial of service, information exposure, or code execution.

Common consequences· 3

Confidentiality — Read Memory
If the expired pointer is used in a read operation, an attacker might be able to control data read in by the application.
Availability — DoS: Crash, Exit, or Restart
If the expired pointer references a memory location that is not accessible to the product, or points to a location that is "malformed" (such as NULL) or larger than expected by a read or write operation, then a crash may occur.
Integrity / Confidentiality / Availability — Execute Unauthorized Code or Commands
If the expired pointer is used in a function call, or points to unexpected data in a write operation, then code execution may be possible.

Potential mitigations· 2

[Architecture and Design]Choose a language that provides automatic memory management.
[Implementation]When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.