/usr/lib/x86_64-linux-gnu/libSrvAuth.so is in libroot-net-auth-dev 5.34.19+dfsg-1.2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/root5.34/libSrvAuth.so
/usr/lib/x86_64-linux-gnu/root5.34/libSrvAuth.so