For Android, detect Bidirectional Communication by correlating analyst-visible device/network evidence and management state; use streaming or batched telemetry only where the documented collector is deployed. Correlate Application Permission via Android Enterprise DPC / Application Vetting [DevicePolicyManager.getPermissionGrantState(); PackageManager manifest/requested-permission review]; Application State via Android Enterprise / EMM [Managed package inventory/status and package metadata]; File Creation via Application Vetting / Forensic Acquisition [Dynamic filesystem trace or acquired app-container/filesystem artifacts: Local file write between inbound retrieval]. Alert on a sequence or state change inconsistent with the device/app baseline, approved management policy, or expected user workflow; do not infer unobserved API calls, file/process activity, or payload content from management state alone.
| Data Component | Name | Channel |
|---|---|---|
| Application Permission (DC0114) | android:DevicePolicyManager | DevicePolicyManager.getPermissionGrantState(); PackageManager manifest/requested-permission review |
| Application State (DC0123) | android:EMM | Managed package inventory/status and package metadata |
| File Creation (DC0039) | mobile:ForensicArtifacts | Dynamic filesystem trace or acquired app-container/filesystem artifacts: Local file write between inbound retrieval |
| Network Traffic Content (DC0085) | webproxy:applog | DNS/HTTP(S) inspection or proxy transaction metadata where enterprise decryption/inspection is deployed |
| OS API Execution (DC0021) | mobile:DynamicAnalysis | Dynamic API/runtime trace: Background scheduler or persistent service triggers retrieve-then-write cycle |
| Field | Description |
|---|---|
| ApprovedPlatformApps | Apps approved for bidirectional use of each platform: note-taking app for its own cloud, email app for its service. Non-platform apps doing read-then-write cycles are anomalous. |
| BidirectionalCycleWindow | Default 120s between inbound retrieval and outbound write constituting one C2 cycle. Tightening: 30s. |
| CycleCountThreshold | Default 3 retrieve-write cycles within $ObservationWindow$. Single cycle may be legitimate; repeated cycles are C2 pattern. |
| ObservationWindow | Default 3600s. |
For iOS, detect Bidirectional Communication by correlating analyst-visible device/network evidence and management state; use streaming or batched telemetry only where the documented collector is deployed. Correlate Application Permission via Application Vetting [Code-signing entitlements and Info.plist privacy usage-description keys]; Application State via Apple MDM [InstalledApplicationList / ManagedApplicationList]; Network Traffic Content via Enterprise Secure Web Gateway / Proxy [DNS/HTTP(S) inspection or proxy transaction metadata where enterprise decryption/inspection is deployed]. Alert on a sequence or state change inconsistent with the device/app baseline, approved management policy, or expected user workflow; do not infer unobserved API calls, file/process activity, or payload content from management state alone.
| Data Component | Name | Channel |
|---|---|---|
| Application Permission (DC0114) | mobile:ApplicationVetting | Code-signing entitlements and Info.plist privacy usage-description keys |
| Application State (DC0123) | iOS:MDM | InstalledApplicationList / ManagedApplicationList |
| Network Traffic Content (DC0085) | webproxy:applog | DNS/HTTP(S) inspection or proxy transaction metadata where enterprise decryption/inspection is deployed |
| OS API Execution (DC0021) | mobile:DynamicAnalysis | Dynamic API/runtime trace: Background task activation immediately before retrieve-then-write cycle on supervised device |
| Field | Description |
|---|---|
| ApprovedPlatformApps | Apps approved for bidirectional use of each platform: note-taking app for its own cloud, email app for its service. Non-platform apps doing read-then-write cycles are anomalous. |
| BidirectionalCycleWindow | Default 120s between inbound retrieval and outbound write constituting one C2 cycle. Tightening: 30s. |
| CycleCountThreshold | Default 3 retrieve-write cycles within $ObservationWindow$. Single cycle may be legitimate; repeated cycles are C2 pattern. |
| ObservationWindow | Default 3600s. |