In devs.c in Yubico libu2f-host before 1.1.8, the response to init is misparsed, leaking uninitialized stack memory back to the device.
https://security.gentoo.org/glsa/202004-15
https://github.com/Yubico/libu2f-host/commit/e4bb58cc8b6202a421e65f8230217d8ae6e16eb5
https://developers.yubico.com/libu2f-host/Release_Notes.html
https://blog.inhq.net/posts/yubico-libu2f-host-vuln-part2/
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00018.html
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00012.html