NoMachine External Control of File Path Arbitrary File Deletion Vulnerability. This vulnerability allows local attackers to delete arbitrary files on affected installations of NoMachine. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the handling of environment variables. The issue results from the lack of proper validation of a user-supplied path prior to using it in file operations. An attacker can leverage this vulnerability to delete files in the context of root. Was ZDI-CAN-28644.