/usr/share/doc/mailcrypt/HTML/ is in mailcrypt 3.5.9-7.
This file is owned by root:root, with mode 0o755.
..
/usr/share/doc/mailcrypt/HTML/index.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_0.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_1.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_10.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_2.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_3.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_4.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_5.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_6.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_7.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_8.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_9.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_abt.html
/usr/share/doc/mailcrypt/HTML/mailcrypt_toc.html