CWE-910

Base Abstraction Level
Pillar — Highest-level weakness category
Class — Abstract, language-independent
Base — Specific enough to detect
Variant — Tied to specific technology
Compound — Requires multiple weaknesses Incomplete MITRE CWE Status
Stable — Fully reviewed and complete
Draft — Under development, may change
Incomplete — Partially defined by MITRE
Deprecated — No longer recommended
Obsolete — Replaced by another CWE Exploit: Medium
Use of Expired File Descriptor

Description

The product uses or accesses a file descriptor after it has been closed.

After a file descriptor for a particular file or device has been released, it can be reused. The code might not write to the original file, since the reused file descriptor might reference a different file or device.

Consequences

Confidentiality — Read Files or Directories

The program could read data from the wrong file.

Availability — DoS: Crash, Exit, or Restart

Accessing a file descriptor that has been closed can cause a crash.

Detection

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.)