CWE WEAKNESSES / CWE-825
CWE-825
Expired Pointer Dereference
Base
What it is
The product dereferences a pointer that contains a location for memory that was previously valid, but is no longer valid.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.
Impact
| Confidentiality | Read Memory |
| Availability | DoS: Crash, Exit, or Restart |
| Integrity, Confidentiality, Availability | Execute Unauthorized Code or Commands |
Mitigations
- [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.
Real-world CVE examples
- CVE-2023-26463 — Chain: IPSec VPN product uses the same variable for multiple purposes in the same function (CWE-1109), leading to incorrect access control (CWE-284) and expired
- CVE-2008-5013 — access of expired memory address leads to arbitrary code execution
- CVE-2010-3257 — stale pointer issue leads to denial of service and possibly other consequences
- CVE-2008-0062 — Chain: a message having an unknown message type may cause a reference to uninitialized memory resulting in a null pointer dereference (CWE-476) or dangling poin
- CVE-2007-1211 — read of value at an offset into a structure after the offset is no longer valid
Related weaknesses
Test & detect
Browse all common weaknesses, check related exploited CVEs, or map to ATT&CK techniques.
Source: MITRE CWE. View on cwe.mitre.org →