CWE-1109: Use of Same Variable for Multiple Purposes
Official CWE-1109 CWE context with Glexia analysis, remediation guidance, related CVEs, and ATT&CK context.
Glexia's Take
CWE-1109: Use of Same Variable for Multiple Purposes
Use of Same Variable for Multiple Purposes represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Executive Impact
- Other: Reduce Maintainability: This issue makes it more difficult to maintain the product, which indirectly affects security by making it more difficult or time-consuming to find and/or fix vulnerabilities. It also might make it easier to introduce vulnerabilities.
- Other: Increase Analytical Complexity: Use of the same variable for multiple purposes can make it more difficult for a person to read or understand the code, potentially hiding other quality issues.
Developer Pattern
CWE-1109 is the kind of defect developers can usually prevent with explicit validation, safer framework defaults, and tests that exercise hostile input or unsafe state transitions.
Confidence
high confidence from CWE-1109, 4.20.
Official CWE Definition
CWE-1109: Use of Same Variable for Multiple Purposes
The code contains a callable, block, or other code element in which the same variable is used to control more than one unique task or store more than one instance of data.
Developer And Remediation Guidance
How teams prevent and detect this weakness
Causes
- Missing validation
- Unsafe defaults
- Insufficient authorization or memory-safety invariant
Remediation
- Use safe APIs
- Centralize the control
- Add regression tests
- Review logs and telemetry for attempted abuse
Detection
- Code review
- SAST
- DAST
- Focused regression tests
Mappings
Related CVEs, CWEs, and ATT&CK context
ATT&CK Relevance
ATT&CK relevance is shown only when reviewed or responsibly inferred.