Table of Contents
Red Hat Product Security has rated this issue as having Low severity. An attacker could use this flaw to determine whether given usernames exist or not on the server, but no further information is disclosed and there is no availability or integrity impact. A future update may address this issue.
CVSS v3 metrics
NOTE: The following CVSS v3 metrics and score provided are preliminary and subject to review.
|CVSS3 Base Score||5.3|
|CVSS3 Base Metrics||CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N|
Affected Packages State
|Red Hat Enterprise Linux 7||openssh||Affected|
|Red Hat Enterprise Linux 6||openssh||Will not fix|
|Red Hat Enterprise Linux 5||openssh||Will not fix|
Configuring your firewall to limit the origin and/or rate of incoming ssh connections (using the netfilter xt_recent module) will limit the impact of this attack, as it requires a new TCP connection for each username tested. This configuration also provides some protection against brute-force attacks on SSH passwords or keys.
See the following article for more information on limiting access to SSHD: https://access.redhat.com/solutions/8687
CVE description copyright © 2017, The MITRE Corporation