Detection of Data Encrypted for Impact

ID: DET0678
Domains: Mobile
Analytics: AN1781
Version: 1.0
Created: 21 October 2025
Last Modified: 21 October 2025

Analytics

AN1781

An application with access to broad file scopes or sensitive storage areas becomes active, performs abnormal burst file reads and writes across many user or shared-storage locations, transforms file content or extensions at scale in a short window, and causes rapid file inaccessibility, rewrite, or replacement inconsistent with normal sync, backup, media processing, or document-editing behavior. The defender correlates capability state, app lifecycle, framework use, bulk file-write effects, and optional network communications to distinguish encrypt-for-impact behavior from benign bulk file operations.

Log Sources
Data Component Name Channel
Protected Configuration (DC0115) android:MDMLog Managed storage, backup, enterprise file access, or device policy state remains unchanged while bulk destructive file transformation occurs
Application Permission (DC0114) MobileEDR:telemetry Application holds or is granted broad storage, document-provider, media, or file-management capability inconsistent with its expected role before or during bulk file transformation
Application State (DC0123) MobileEDR:telemetry Application runs in foreground, service, or sustained background-active state while concentrated file transformation occurs with weak or no recent user interaction
OS API Execution (DC0021) MobileEDR:telemetry Content resolver, document provider, media store, storage access framework, bulk stream processing, or repeated crypto-adjacent framework use observed during multi-file transformation
Mutable Elements
Field Description
TimeWindow Maximum correlation span between app activation, framework use, and burst file transformation.
AllowedAppList Approved apps allowed to perform legitimate broad file operations such as backup, sync, AV scanning, enterprise migration, media editing, or document management.
ForegroundStateRequired Whether a benign bulk file operation is expected to occur only while the app is visible and actively used.
RecentUserInteractionWindow Threshold for determining whether large-scale file transformation was user-driven versus unattended.
FileWriteBurstThreshold Threshold for number of file create, overwrite, rename, or replace actions within the correlation window.
DistinctDirectoryThreshold Threshold for number of distinct folders or content roots touched during the file-impact burst.
ExtensionChangeThreshold Threshold for suspicious file extension changes or replacement-file patterns indicative of mass transformation.
BytesWrittenThreshold Threshold for cumulative bytes written during the impact window.
ProtectedPathAllowList Known paths, document roots, or work-profile storage locations where benign enterprise migration or sync tooling may rewrite many files.
DestinationAllowList Expected network destinations contacted by legitimate storage, sync, backup, or MDM remediation apps.