The NSS update 3.18 included a new version of the root CA list, version 2.3 https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.18_release_notes
ca-certificates-2015.2.3-1.0.fc22 has been submitted as an update for Fedora 22. https://admin.fedoraproject.org/updates/ca-certificates-2015.2.3-1.0.fc22
ca-certificates-2015.2.3-1.0.fc21 has been submitted as an update for Fedora 21. https://admin.fedoraproject.org/updates/ca-certificates-2015.2.3-1.0.fc21
ca-certificates-2015.2.3-1.0.fc20 has been submitted as an update for Fedora 20. https://admin.fedoraproject.org/updates/ca-certificates-2015.2.3-1.0.fc20
Package ca-certificates-2015.2.3-1.0.fc20: * should fix your issue, * was pushed to the Fedora 20 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing ca-certificates-2015.2.3-1.0.fc20' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/FEDORA-2015-4486/ca-certificates-2015.2.3-1.0.fc20 then log in and leave karma (feedback).
ca-certificates-2015.2.3-1.0.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.