Weakness · Medium
CWE-663: Use of a Non-reentrant Function in a Concurrent Context
What it is
The product calls a non-reentrant function in a concurrent context in which a competing code sequence (e.g. thread or signal handler) may have an opportunity to call the same function or otherwise influence its state.
- Severity (our rating)
- Medium
- Likelihood of exploit
- Not rated by MITRE
- Introduced during
- Implementation
- Exploited in the wild
- No CVE in CISA's catalog
What an attacker can do
- Modify Memory (Integrity, Confidentiality, Other)
- Read Memory (Integrity, Confidentiality, Other)
- Modify Application Data (Integrity, Confidentiality, Other)
- Read Application Data (Integrity, Confidentiality, Other)
- Alter Execution Logic (Integrity, Confidentiality, Other)
How to prevent it
Implementation
- Use reentrant functions if available.
- Add synchronization to your non-reentrant function.
- In Java, use the ReentrantLock Class.
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.