Time-of-check Time-of-use (TOCTOU) Race Condition
file.copy operations in GruntJS are vulnerable to a TOCTOU race condition leading to arbitrary file write in versions prior to 1.5.3. This vulnerability is capable of arbitrary file writes which can lead to local privilege escalation to the GruntJS user if a lower-privileged user has write access to both source and destination directories as the lower-privileged user can create a symlink to the GruntJS user's .bashrc file or replace /etc/shadow file if the GruntJS user is root.
CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
The software checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the software to perform invalid actions when the resource is in an unexpected state.