Suspicious PowerShell and MSBuild Activity with Defense Evasion and Persistence
This rule detects several suspicious activities often associated with post-exploitation and defense evasion. It identifies PowerShell commands used for recursively searching for msbuild.exe, tampering with Windows Defender settings (disabling real-time monitoring or adding exclusions), and downloading files from the internet to common temporary or application data directories. Additionally, it flags msbuild.exe executing suspicious .proj files from temporary directories, and any executable launched from temporary or program data folders by PowerShell or MSBuild. The rule also includes detection for persistence via .url file creation in the Startup folder and the dropping of specific suspicious files (.proj, pins.dat, staxs.exe, tybd7.exe) by PowerShell or MSBuild in temporary or program data directories.
Microsoft Sentinel (KQL)
