Weakness · Medium
CWE-393: Return of Wrong Status Code
What it is
A function or operation returns an incorrect return value or status code that does not indicate the true result of execution, causing the product to modify its behavior based on the incorrect result.
- Severity (our rating)
- Medium
- Likelihood of exploit
- Not rated by MITRE
- Introduced during
- Implementation
- Exploited in the wild
- No CVE in CISA's catalog
In more detail
This can lead to unpredictable behavior. If the function is used to make security-critical decisions or provide security-critical information, then the wrong status code can cause the product to assume that an action is safe or correct, even when it is not.
What an attacker can do
- Unexpected State (Integrity, Other)
- Alter Execution Logic (Integrity, Other)
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
- Fuzzing. Fuzz testing (fuzzing) is a powerful technique for generating large numbers of diverse inputs - either randomly or algorithmically - and dynamically invoking the code with those inputs. Even with random inputs, it is often capable of generating unexpected results such as crashes, memory corruption, or resource consumption. Fuzzing effectively produces repeatable test cases that clearly indicate bugs, which helps developers to diagnose the issues.
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.