There is a SEGV in Exiv2::Internal::TiffParserWorker::findPrimaryGroups of tiffimage_int.cpp in Exiv2 0.27-RC3. A crafted input will lead to a remote denial of service attack.
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2018-20097.json"