Title

The SSH daemon must ignore .rhosts files. (Cat II impact)

Discussion

SSH trust relationships mean a compromise on one host can allow an attacker to move trivially to other hosts.

Check Content

To determine how the SSH daemon's "IgnoreRhosts" option is set, run the following command: # grep -i IgnoreRhosts /etc/ssh/sshd_config If no line, a commented line, or a line indicating the value "yes" is returned, then the required value is set. If the required value is not set, this is a finding.

Fix Text

SSH can emulate the behavior of the obsolete rsh command in allowing users to enable insecure access to their accounts via ".rhosts" files. To ensure this behavior is disabled, add or correct the following line in "/etc/ssh/sshd_config": IgnoreRhosts yes

Additional Identifiers

Rule ID: SV-217998r603264_rule

Vulnerability ID: V-217998

Group Title: SRG-OS-000106

Expert Comments

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