/usr/share/icons/oxygen/256x256/mimetypes/application-x-sharedlib.png is in oxygen-icon-theme-complete 4:4.8.2-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/icons/oxygen/256x256/mimetypes/application-x-python-bytecode.png