AccountFoundation can either create AWS detective services (GuardDuty for threat detection, Security Hub for compliance dashboards) or reuse pre-existing ones via opt-in flags. The reuse paths just imported the existing resources and reported success — they never checked whether the existing services were actually doing their job.
GuardDuty reuse. If the existing detector was suspended, or set to the slower 6-hour publishing cadence instead of the baseline 15-minute one, or otherwise misconfigured — Hulumi never noticed. The deployment succeeded with a misleadingly-positive guardDutyDetectorId output as if the baseline were active.
Security Hub reuse. Although the account import was read-only, Hulumi unconditionally created the CIS / NIST StandardsSubscription resources with default delete behaviour. Pulumi then treated those subscriptions as its own — a later pulumi destroy of the stack would call BatchDisableStandards, unsubscribing the account from CIS / NIST compliance monitoring even on accounts that had those subscriptions before Hulumi ever ran.
Impact
Consumers using AccountFoundation's reuse mode could:
ship deployments that appeared to enable a detective baseline but actually weren't (case 1), or
accidentally turn off CIS / NIST compliance monitoring on an existing account just by destroying a Hulumi stack (case 2 — no malicious intent needed; a normal stack teardown was enough).
GuardDuty reuse now asserts the imported detector is ENABLED with findingPublishingFrequency: FIFTEEN_MINUTES. Wrong posture fails the deploy at preview time.
Security Hub reuse creates the CIS / NIST StandardsSubscription resources with , so destroying a reused stack no longer unsubscribes the account.
retainOnDelete: true
Net-new (non-reuse) deployments are unchanged.
Workarounds
Don't reuse pre-existing detective services with AccountFoundation before upgrading. If reuse is unavoidable, manually verify detector posture out-of-band.
Resources
PR #178 (Cluster G); regression tests in
packages/baseline/tests/guardduty-reuse-posture.test.ts and
packages/baseline/tests/securityhub-reuse-retain.test.ts.