Back to results

Potential Evasion via Boot Time Removal Tool

Identifies creation of a ":changelist" NTFS alternate data stream or a Windows service Args registry value pointing to a ":changelist" path. Microsoft Defender's Boot-Time Removal (BTR.sys) driver reads an…

Description

Identifies creation of a ":changelist" NTFS alternate data stream or a Windows service Args registry value pointing to a ":changelist" path. Microsoft Defender's Boot-Time Removal (BTR.sys) driver reads an RC4-encrypted transaction blob from a driver ADS named ":changelist", referenced by HKLM\SYSTEM\*ControlSet*\Services\*\Args. Adversaries can reproduce this staging outside Defender to abuse BTR.sys as a signed kernel primitive for arbitrary file and registry operations. This rule focuses on non-System writers and excludes Microsoft-signed MRT.exe running as SYSTEM, which may perform related remediation staging.

Detection logic

Its licence does not clear it for publishing here

Sunturai publishes a detection's own text where the licence it arrived under has been reviewed and permits it, and Elastic License 2.0 has not. The query as its source wrote it, its canonical form and the hash that pins this revision are in the workspace record.

Detection requirements

Platform
ContainersESXiIaaSIdentity ProviderLinuxmacOSNetwork DevicesOffice SuiteWindows

The rule states no platform. This is derived from the 4 ATT&CK techniques it maps to.

Detections can measure how the public catalogue is used — which detections people look for, and which pages bring them here. It sets a cookie that recognises this browser for 180 days. It is never linked to an account and never follows you to other sites. Privacy notice