Title

The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon performs strict mode checking of home directory configuration files. (Cat II impact)

Discussion

If other users have access to modify user-specific SSH configuration files, they may be able to log on to the system as another user.

Check Content

Verify the SSH daemon performs strict mode checking of home directory configuration files. The location of the "sshd_config" file may vary if a different daemon is in use. Inspect the "sshd_config" file with the following command: # grep -i strictmodes /etc/ssh/sshd_config StrictModes yes If "StrictModes" is set to "no", is missing, or the returned line is commented out, this is a finding.

Fix Text

Uncomment the "StrictModes" keyword in "/etc/ssh/sshd_config" (this file may be named differently or be in a different location if using a version of SSH that is provided by a third-party vendor) and set the value to "yes": StrictModes yes The SSH service must be restarted for changes to take effect.

Additional Identifiers

Rule ID: SV-204600r991589_rule

Vulnerability ID: V-204600

Group Title: SRG-OS-000480-GPOS-00227

Expert Comments

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