rcp on various Linux systems including Red Hat 4.0 allows a "nobody" user or other user with UID of 65535 to overwrite arbitrary files, since 65535 is interpreted as -1 by chown and other system calls, which causes the calls to fail to modify the ownership of the file.
abuse.console in Red Hat 2.1 uses relative pathnames to find and execute the undrv program, which allows local users to execute arbitrary commands via a path that points to a Trojan horse program.