/usr/include/hcrypto/rc4.h is in heimdal-dev 1.6~rc2+dfsg-9+deb8u1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/include/hcrypto/../heimdal/hcrypto/rc4.h
/usr/include/hcrypto/../heimdal/hcrypto/rc4.h