Detection of Calendar Entries

Technique Detected:  Calendar Entries | T1636.001

ID: DET0674
Domains: Mobile
Analytics: AN1774, AN1775
Version: 1.0
Created: 21 October 2025
Last Modified: 12 May 2026

Analytics

AN1774

For Android, detect Calendar Entries by correlating analyst-visible device/network evidence and management state; use streaming or batched telemetry only where the documented collector is deployed. Correlate API Calls via Application Vetting / Instrumented Dynamic Analysis [Dynamic API/runtime trace: ContentResolver.query(CalendarContract) with query_count > $CalendarQueryThreshold$ by app NOT IN $ApprovedCalendarApps$]; Network Traffic Flow via Android Enterprise Network Logging / Enterprise VPN [DevicePolicyManager.retrieveNetworkLogs(): DnsEvent / ConnectEvent; VPN flow metadata]; Permissions Request via Android Enterprise DPC / Application Vetting [DevicePolicyManager.getPermissionGrantState(); PackageManager manifest/requested-permission review]. 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.

Log Sources
Data Component Name Channel
API Calls (DC0112) mobile:DynamicAnalysis Dynamic API/runtime trace: ContentResolver.query(CalendarContract) with query_count > $CalendarQueryThreshold$ by app NOT IN $ApprovedCalendarApps$
Network Traffic Flow (DC0078) android:EnterpriseNetworkLog DevicePolicyManager.retrieveNetworkLogs(): DnsEvent / ConnectEvent; VPN flow metadata
Permissions Request (DC0116) android:DevicePolicyManager DevicePolicyManager.getPermissionGrantState(); PackageManager manifest/requested-permission review
Mutable Elements
Field Description
ApprovedCalendarApps Exchange, Google Calendar, enterprise calendar sync apps.
CalendarQueryThreshold Default 30 queries/2min. Tune per calendar sync app baseline.
CalendarUplinkThreshold Default 50KB — ~25 calendar events average ~2KB each.
CalendarSyncCDNList O365, Google Calendar API endpoints.
ExfilWindow Default 120s.

AN1775

For iOS, detect Calendar Entries by correlating analyst-visible device/network evidence and management state; use streaming or batched telemetry only where the documented collector is deployed. Correlate API Calls via Application Vetting / Instrumented Dynamic Analysis [Dynamic API/runtime trace: EKEventStore.fetchEvents() or enumerateEvents() with date_range > $CalendarDateRangeThreshold$ days by app NOT IN $ApprovedCalendarApps$]; Network Traffic Flow via Apple Network Extension / Enterprise VPN [NEFilterFlow / per-app VPN / secure-web-gateway flow metadata]; Permissions Request via Application Vetting [Code-signing entitlements and Info.plist privacy usage-description keys]. 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.

Log Sources
Data Component Name Channel
API Calls (DC0112) mobile:DynamicAnalysis Dynamic API/runtime trace: EKEventStore.fetchEvents() or enumerateEvents() with date_range > $CalendarDateRangeThreshold$ days by app NOT IN $ApprovedCalendarApps$
Network Traffic Flow (DC0078) iOS:NetworkExtension NEFilterFlow / per-app VPN / secure-web-gateway flow metadata
Permissions Request (DC0116) mobile:ApplicationVetting Code-signing entitlements and Info.plist privacy usage-description keys
Mutable Elements
Field Description
ApprovedCalendarApps com.microsoft.outlook, com.google.calendar.app, enterprise calendar bundles.
CalendarDateRangeThreshold Default 365 days — full-store fetch vs incremental sync.
CalendarUplinkThreshold Default 50KB.
CalendarSyncCDNList O365, Google Calendar API endpoints.
ExfilWindow Default 120s.