AMSI Bypass via .NET Reflection on Non-Public AmsiUtils Fields

Ibrahim Saud@tektrix

•updated Jun 29, 2026•0•0•5

Detects the use of PowerShell .NET reflection to access non-public static fields within the System.Management.Automation.AmsiUtils class. Attackers often target fields such as 'amsiInitFailed' or 's_amsiContext' to programmatically disable or bypass Antimalware Scan Interface (AMSI) inspection during script execution.