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Patterns
Fiction Lab / PatternAmbiguous

The safeguards that share one assumption

Mechanism

Several controls look independent but depend on the same data, service, supplier, team or model family.

Enabling conditions

  • Complex architecture hides shared services
  • Assurance counts controls rather than dependencies

Failure modes

  • One failure disables several barriers
  • Redundancy exists only on a diagram

Early signals

  • • Independent controls fail together in tests
  • • Several alerts disappear with one service

Countermeasures

  • • Map common dependencies
  • • Test loss of assumptions

Diagnostic questions

  1. 1.Which controls share one dependency?
  2. 2.How is unknown represented?