Weakness · Medium
CWE-462: Duplicate Key in Associative List (Alist)
What it is
Duplicate keys in associative lists can lead to non-unique keys being mistaken for an error.
- Severity (our rating)
- Medium
- Likelihood of exploit
- Low
- Introduced during
- Implementation
- Exploited in the wild
- No CVE in CISA's catalog
In more detail
A duplicate key entry -- if the alist is designed properly -- could be used as a constant time replace function. However, duplicate key entries could be inserted by mistake. Because of this ambiguity, duplicate key entries in an association list are not recommended and should not be allowed.
What an attacker can do
- Quality Degradation (Other)
- Varies by Context (Other)
How to prevent it
Architecture and Design
- Use a hash table instead of an alist.
- Use an alist which checks the uniqueness of hash keys with each entry before inserting the entry.
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.