CVE-2026-48036

Hulumi is an open-source toolkit that ships secure-by-default cloud and platform infrastructure components for Pulumi. Prior to version 1.4.0, consumers running drift detection in CI / cron could see transient adapter failures silently cached as "all clear" — masking real attacks for up to six hours — or see ordinary provider-version churn falsely promoted to incident severity. Either way, the verdict source was unreliable for downstream incident workflows that gate on it. This issue has been patched in version 1.4.0.

Hulumi is an open-source toolkit that ships secure-by-default cloud and platform infrastructure components for Pulumi. Prior to version 1.4.0, consumers running drift detection in CI / cron could see transient adapter failures silently cached as "all clear" — masking real attacks for up to six hours — or see ordinary provider-version churn falsely promoted to incident severity. Either way, the verdict source was unreliable for downstream incident workflows that gate on it. This issue has been patched in version 1.4.0.

Affected: @hulumi/drift < 1.4.0 — Fixed in: 1.4.0 — Severity: Medium — CWE-755 (Improper Handling of Exceptional Conditions)

Summary

@hulumi/drift runs four adapters that each ask a different question about whether a resource has drifted (Pulumi-state diff, provider-version change, CloudTrail event, etc.). A classifier combines the adapters' answers into a verdict like None / none, ConsoleBreakGlass / high, or Mixed / high, and caches the verdict for 6 hours by default.

Two related bugs from one root cause — the classifier only read each adapter's detected: true/false field and ignored whether the adapter itself succeeded:

1. Cached "all clear" on adapter failure. When an adapter failed (e.g. transient network error from the Automation API), the classifier read detected: false, concluded "no drift", and cached the verdict as None / none for 6 hours. A single transient failure could mask real console-break-glass mutations for the rest of the window.
2. Mixed verdicts without real evidence. The Mixed / high and ConsoleBreakGlass / high verdicts (incident severity) could fire on the "the CloudTrail probe round-tripped successfully" signal rather than actual evidence that anything had been changed via the console. Normal provider-API churn could end up falsely escalated to incident severity.

Impact

Consumers running drift detection in CI / cron could see transient adapter failures silently cached as "all clear" — masking real attacks for up to six hours — or see ordinary provider-version churn falsely promoted to incident severity. Either way, the verdict source was unreliable for downstream incident workflows that gate on it.

Patches

Upgrade to @hulumi/[email protected]. Classifier-only fix (the TLA+-verified 6-row verdict matrix is byte-identical):

• adapter failures now fail closed to Unknown / low, and degraded verdicts are not written to the cache;
• the Mixed / ConsoleBreakGlass promotion now requires real CloudTrail event evidence rather than probe liveness.

Workarounds

Setting options.minConfidence: "medium" on the classifier call prevents the degraded None / none from being cached (it doesn't meet the threshold), partially mitigating case (1). No workaround for case (2).

Resources

• PR #178 (Cluster D); regression tests in packages/drift/tests/classifier-fail-closed.test.ts.

Hulumi is an open-source toolkit that ships secure-by-default cloud and platform infrastructure components for Pulumi. Prior to version 1.4.0, consumers running drift detection in CI / cron could see transient adapter failures silently cached as "all clear" — masking real attacks for up to six hours — or see ordinary provider-version churn falsely promoted to incident severity. Either way, the verdict source was unreliable for downstream incident workflows that gate on it. This issue has been patched in version 1.4.0.

Hulumi is an open-source toolkit that ships secure-by-default cloud and platform infrastructure components for Pulumi. Prior to version 1.4.0, consumers running drift detection in CI / cron could see transient adapter failures silently cached as "all clear" — masking real attacks for up to six hours — or see ordinary provider-version churn falsely promoted to incident severity. Either way, the verdict source was unreliable for downstream incident workflows that gate on it. This issue has been patched in version 1.4.0.

Affected: @hulumi/drift < 1.4.0 — Fixed in: 1.4.0 — Severity: Medium — CWE-755 (Improper Handling of Exceptional Conditions)

Summary

@hulumi/drift runs four adapters that each ask a different question about whether a resource has drifted (Pulumi-state diff, provider-version change, CloudTrail event, etc.). A classifier combines the adapters' answers into a verdict like None / none, ConsoleBreakGlass / high, or Mixed / high, and caches the verdict for 6 hours by default.

Two related bugs from one root cause — the classifier only read each adapter's detected: true/false field and ignored whether the adapter itself succeeded:

1. Cached "all clear" on adapter failure. When an adapter failed (e.g. transient network error from the Automation API), the classifier read detected: false, concluded "no drift", and cached the verdict as None / none for 6 hours. A single transient failure could mask real console-break-glass mutations for the rest of the window.
2. Mixed verdicts without real evidence. The Mixed / high and ConsoleBreakGlass / high verdicts (incident severity) could fire on the "the CloudTrail probe round-tripped successfully" signal rather than actual evidence that anything had been changed via the console. Normal provider-API churn could end up falsely escalated to incident severity.

Impact

Consumers running drift detection in CI / cron could see transient adapter failures silently cached as "all clear" — masking real attacks for up to six hours — or see ordinary provider-version churn falsely promoted to incident severity. Either way, the verdict source was unreliable for downstream incident workflows that gate on it.

Patches

Upgrade to @hulumi/[email protected]. Classifier-only fix (the TLA+-verified 6-row verdict matrix is byte-identical):

• adapter failures now fail closed to Unknown / low, and degraded verdicts are not written to the cache;
• the Mixed / ConsoleBreakGlass promotion now requires real CloudTrail event evidence rather than probe liveness.

Workarounds

Setting options.minConfidence: "medium" on the classifier call prevents the degraded None / none from being cached (it doesn't meet the threshold), partially mitigating case (1). No workaround for case (2).

Resources

• PR #178 (Cluster D); regression tests in packages/drift/tests/classifier-fail-closed.test.ts.