openssh is vulnerable to information disclosure attacks. The vulnerability exists as sshd in OpenSSH before 7.3, when SHA256 or SHA512 are used for user password hashing, uses BLOWFISH hashing on a static password when the username does not exist, which allows remote attackers to enumerate users by leveraging the timing difference between responses when a large password is provided.
seclists.org/fulldisclosure/2016/Jul/51
www.debian.org/security/2016/dsa-3626
www.securityfocus.com/bid/91812
www.securitytracker.com/id/1036319
access.redhat.com/errata/RHSA-2017:2029
access.redhat.com/errata/RHSA-2017:2563
access.redhat.com/security/updates/classification/#moderate
cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf
security.gentoo.org/glsa/201612-18
security.netapp.com/advisory/ntap-20190206-0001/
www.exploit-db.com/exploits/40113/
www.exploit-db.com/exploits/40136/
www.openssh.com/txt/release-7.3