An issue was discovered in rcp in NetKit through 0.17. For an rcp operation, the server chooses which files/directories are sent to the client. However, the rcp client only performs cursory validation of the object name returned. A malicious rsh server (or Man-in-The-Middle attacker) can overwrite arbitrary files in a directory on the rcp client machine. This is similar to CVE-2019-6111.

In NetKit through 0.17, rcp.c in the rcp client allows remote rsh servers to bypass intended access restrictions via the filename of . or an empty filename. The impact is modifying the permissions of the target directory on the client side. This is similar to CVE-2018-20685.