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CWE-462 — Duplicate Key in Associative List (Alist)

provenance: imported · CWE: CWE-462

CWE-462: Duplicate Key in Associative List (Alist)

MITRE CWE weakness

Kind Weakness
Abstraction Variant
Status Incomplete
Likelihood of exploit Low

Description

Duplicate keys in associative lists can lead to non-unique keys being mistaken for an error.

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.

Common consequences

  • Other: Quality Degradation, Varies by Context

Mitigations

Architecture and Design — Use a hash table instead of an alist.

Architecture and Design — Use an alist which checks the uniqueness of hash keys with each entry before inserting the entry.

References

  • CWE page: https://cwe.mitre.org/data/definitions/462.html
  • CWE list: https://cwe.mitre.org/data/index.html