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V-282711

CAT II (Medium)

The TOSS 5 SSH daemon must not allow rhosts authentication.

Rule ID

SV-282711r1201373_rule

STIG

Tri-Lab Operating System Stack (TOSS) 5 Security Technical Implementation Guide

Version

V1R1

CCIs

CCI-000366

Discussion

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

Check Content

Verify the SSH daemon does not allow rhosts authentication using the following command:

$ sudo /usr/sbin/sshd -dd 2>&1 | awk '/filename/ {print $4}' | tr -d '\r' | tr '\n' ' ' | xargs sudo grep -iH '^\s*ignorerhosts'

IgnoreRhosts yes

If the value is returned as "no", the returned line is commented out, or no output is returned, this is a finding.

Fix Text

Configure the SSH daemon to not allow rhosts authentication.

Add the following line in "/etc/ssh/sshd_config" or uncomment the line and set the value to "yes":

IgnoreRhosts yes

Restart the SSH service for changes to take effect:

$ sudo systemctl restart sshd.service