The SUSE operating system SSH daemon private host key files must have mode 0640 or less permissive.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-235009	SLES-15-040250	SV-235009r880958_rule		Medium

Description
If an unauthorized user obtains the private SSH host key file, the host could be impersonated.

STIG	Date
SUSE Linux Enterprise Server 15 Security Technical Implementation Guide	2023-03-08

Details

Check Text ( C-38197r880956_chk )
Verify the SUSE operating system SSH daemon private host key files have mode "0640" or less permissive. The following command will find all SSH private key files on the system: > sudo find / -name 'ssh_hostkey' -exec ls -lL {} \; Check the mode of the private host key files under "/etc/ssh" file with the following command: > find /etc/ssh -name 'ssh_host*key' -exec stat -c "%a %n" {} \; 640 /etc/ssh/ssh_host_rsa_key 640 /etc/ssh/ssh_host_dsa_key 640 /etc/ssh/ssh_host_ecdsa_key 640 /etc/ssh/ssh_host_ed25519_key If any file has a mode more permissive than "0640", this is a finding.

Check Text ( C-38197r880956_chk )

Verify the SUSE operating system SSH daemon private host key files have mode "0640" or less permissive.

The following command will find all SSH private key files on the system:

> sudo find / -name '*ssh_host*key' -exec ls -lL {} \;

Check the mode of the private host key files under "/etc/ssh" file with the following command:

> find /etc/ssh -name 'ssh_host*key' -exec stat -c "%a %n" {} \;

640 /etc/ssh/ssh_host_rsa_key
640 /etc/ssh/ssh_host_dsa_key
640 /etc/ssh/ssh_host_ecdsa_key
640 /etc/ssh/ssh_host_ed25519_key

If any file has a mode more permissive than "0640", this is a finding.

Fix Text (F-38160r880957_fix)
Configure the mode of the SUSE operating system SSH daemon private host key files under "/etc/ssh" to "0640" with the following command: > sudo chmod 0640 /etc/ssh/ssh_host*key