OpenSSH S/KEY Authentication Enumeration
OpenSSH 4.6 and earlier, when ChallengeResponseAuthentication is enabled, allows remote attackers to determine the existence of user accounts by attempting to authenticate via S/KEY, which displays a different response if the user account exists, a similar issue to CVE-2001-1483.
Unitrends Risk Assessment: None. Not vulnerable.
The OpenSSH packages as shipped with Red Hat Enterprise Linux do not contain S/KEY support.
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