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CWE-342 — Predictable Exact Value from Previous Values

provenance: imported · CWE: CWE-342

CWE-342: Predictable Exact Value from Previous Values

MITRE CWE weakness

Kind Weakness
Abstraction Base
Status Draft
Likelihood of exploit

Description

An exact value or random number can be precisely predicted by observing previous values.

Common consequences

  • Other: Varies by Context

Mitigations

General — Increase the entropy used to seed a PRNG.

Architecture and Design — Use products or modules that conform to FIPS 140-2 [REF-267] to avoid obvious entropy problems. Consult FIPS 140-2 Annex C ("Approved Random Number Generators").

Implementation — Use a PRNG that periodically re-seeds itself using input from high-quality sources, such as hardware devices with high entropy. However, do not re-seed too frequently, or else the entropy source might block.

References

  • CWE page: https://cwe.mitre.org/data/definitions/342.html
  • CWE list: https://cwe.mitre.org/data/index.html