Current package version (1.050-7) is 3 years old which is missing Cyrillic and Greek support. The latest version (2.020R-ro/1.075R-it) can be found at https://github.com/adobe-fonts/source-sans-pro/releases/tag/2.020R-ro%2F1.075R-it P.S.: bug 1246765 has a patch with updated spec provided by Michael Kuhn.
adobe-source-sans-pro-fonts-2.020-1.fc26 has been submitted as an update to Fedora 26. https://bodhi.fedoraproject.org/updates/FEDORA-2017-7e241b1eb3
adobe-source-sans-pro-fonts-2.020-1.fc27 has been submitted as an update to Fedora 27. https://bodhi.fedoraproject.org/updates/FEDORA-2017-2d76a9b93a
adobe-source-sans-pro-fonts-2.020-1.fc25 has been submitted as an update to Fedora 25. https://bodhi.fedoraproject.org/updates/FEDORA-2017-518643921e
adobe-source-sans-pro-fonts-2.020-1.fc26 has been pushed to the Fedora 26 stable repository. If problems still persist, please make note of it in this bug report.
adobe-source-sans-pro-fonts-2.020-1.fc27 has been pushed to the Fedora 27 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2017-2d76a9b93a
adobe-source-sans-pro-fonts-2.020-1.fc25 has been pushed to the Fedora 25 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2017-518643921e
adobe-source-sans-pro-fonts-2.020-1.fc25 has been pushed to the Fedora 25 stable repository. If problems still persist, please make note of it in this bug report.
adobe-source-sans-pro-fonts-2.020-1.fc27 has been pushed to the Fedora 27 stable repository. If problems still persist, please make note of it in this bug report.