/usr/share/igtf-policy/classic/PK-Grid-2007.crl_url is in igtf-policy-classic 1.79-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1
http://www.ncp.edu.pk/pk-grid-ca/2007/CRL/ncp.crl