Windows Subsystem for Linux (WSL) is a compatibility layer that lets Windows run Linux user-space tools and environments without a full separate virtual machine. It is widely used for command-line work, scripting, development, and testing because it gives Windows users access to familiar Linux utilities, package managers, and shells.
In cybersecurity, WSL matters because it expands the workstation attack surface. Security teams need to consider which users can run it, what filesystems or network resources are exposed to Linux processes, and whether secrets stored on the host can be reached from within WSL. Attackers may abuse WSL to execute Linux tools for reconnaissance, payload staging, or post-exploitation activity on a Windows endpoint. Defenders can monitor WSL activity, restrict permissions, and treat it as part of endpoint hardening, not as a separate trust zone.