você pode tentar jogar com:
-
cmds_allowed
This options specifies a comma separated list of allowed FTP commands (post login. USER, PASS and QUIT and others are always allowed pre-login). Other commands are rejected. This is a powerful method of really locking down an FTP server. Example: cmds_allowed=PASV,RETR,QUIT Default: (none)
-
cmds_denied
This options specifies a comma separated list of denied FTP commands (post login. USER, PASS, QUIT and others are always allowed pre-login). If a command appears on both this and cmds_allowed then the denial takes precedence. (Added in v2.1.0).
e bloqueie o comando RNTO, por exemplo.