/usr/share/igtf-policy/unaccredited/UKPathfinder1.crl_url is in igtf-policy-unaccredited 1.88-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1
http://crl.ca.ngs.ac.uk/crl/pathfinder.crl.der