APPLICATION CONTAINMENT: HOW TO USE RINGFENCING TO PREVENT THE WEAPONIZATION OF TRUSTED SOFTWARE

Summary from the TLDR InfoSec newsletter

Ringfencing extends application allowlisting by enforcing granular containment policies on approved software, controlling file access, registry modifications, inter-process communication, and network activity to prevent “living off the land” attacks that weaponize legitimate tools like PowerShell, Office macros, or scripting engines. The technique blocks lateral movement, data exfiltration, and ransomware encryption by restricting applications to only their necessary functions, preventing them from spawning unauthorized child processes or accessing sensitive directories. Implement ringfencing in phases, starting with high-risk applications, use simulation mode to identify legitimate use cases before enforcement, combine with application allowlisting and storage controls, and continuously monitor the unified audit for policy violations.