The latest OpenSSH update, OpenSSH 7.1p2, disabled experimental client-side roaming support to address a serious information leak flaw. The issue would have let an attacker who had successfully compromised a server to steal credentials from individual clients.
Since version 5.4, the OpenSSH client has had an undocumented feature for resuming SSH connections, aka roaming. If the client’s connection to an SSH server broke unexpectedly and the server supported roaming, the feature would let the client reconnect and resume the interrupted SSH session. Though the corresponding server code was never shipped, roaming was enabled by default in the client code.
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