Weakness · Medium
CWE-910: Use of Expired File Descriptor
What it is
The product uses or accesses a file descriptor after it has been closed.
- Severity (our rating)
- Medium
- Likelihood of exploit
- Medium
- Introduced during
- Implementation
- Exploited in the wild
- No CVE in CISA's catalog
In more detail
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.
What an attacker can do
- Read Files or Directories (Confidentiality)
- DoS: Crash, Exit, or Restart (Availability)
How to prevent it
MITRE lists no specific mitigation for this weakness. Treat it like its parent weaknesses below: validate input, keep the design simple and review the code where it could appear.
How to find it
- 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.)
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.