/usr/lib/ghc-doc/hoogle/libghc-cipher-rc4-doc.txt is in libghc-cipher-rc4-doc 0.1.4-7build7.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-cipher-rc4-doc/html/cipher-rc4.txt