A bind mount is a Linux mount that makes one existing directory appear at another path. Instead of copying data, the kernel presents the same files through a different location in the filesystem tree. The underlying contents are shared, so changes made through either path affect the same directory.
Bind mounts matter in cyber security because they are often used to build sandboxes, containers, and restricted environments. Defenders can expose only approved directories to a process, while hiding the rest of the host filesystem. But bind mounts can also create risk if they are placed in the wrong mount namespace, inherit unsafe permissions, or expose sensitive paths into a jailed environment. In attacks, a misplaced bind mount may let untrusted code reach files it should not see; in defenses, careful bind-mount layout helps enforce least privilege.