/usr/share/xindy/lang/russian/ is in xindy-rules 2.4-1.1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/xindy/lang/russian/cp1251-lang.xdy
/usr/share/xindy/lang/russian/cp1251-test.xdy
/usr/share/xindy/lang/russian/cp1251.xdy
/usr/share/xindy/lang/russian/iso88595-lang.xdy
/usr/share/xindy/lang/russian/iso88595-test.xdy
/usr/share/xindy/lang/russian/iso88595.xdy
/usr/share/xindy/lang/russian/koi8-r-lang.xdy
/usr/share/xindy/lang/russian/koi8-r-test.xdy
/usr/share/xindy/lang/russian/koi8-r.xdy
/usr/share/xindy/lang/russian/translit-iso-utf8-lang.xdy
/usr/share/xindy/lang/russian/translit-iso-utf8-test.xdy
/usr/share/xindy/lang/russian/translit-iso-utf8.xdy
/usr/share/xindy/lang/russian/utf8-lang.xdy
/usr/share/xindy/lang/russian/utf8-test.xdy
/usr/share/xindy/lang/russian/utf8.xdy