OpenStage 60 and OpenScape Desk Phone IP 55G SIP V3, OpenStage 15, 20E, 20 and 40 and OpenScape Desk Phone IP 35G SIP V3, OpenScape Desk Phone IP 35G Eco SIP V3, OpenStage 60 and OpenScape Desk Phone IP 55G HFA V3, OpenStage 15, 20E, 20, and 40 and OpenScape Desk Phone IP 35G HFA V3, and OpenScape Desk Phone IP 35G Eco HFA V3 use non-unique X.509 certificates and SSH host keys.
https://www.kb.cert.org/vuls/id/BLUU-A2PPZE
https://networks.unify.com/security/advisories/OBSO-1511-02.pdf
https://networks.unify.com/security/advisories/OBSO-1511-02-A.pdf