/usr/lib/x86_64-linux-gnu/libopencv_legacy.so.2.4 is in libopencv-legacy2.4v5 2.4.9.1+dfsg1-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libopencv_legacy.so.2.4.9
/usr/lib/x86_64-linux-gnu/libopencv_legacy.so.2.4.9