The SUSE operating system SSH daemon must not allow compression or must only allow compression after successful authentication.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-217279 | SLES-12-030250 | SV-217279r991589_rule | CCI-000366 | medium |
| Description | ||||
| If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection, potentially with root privileges. | ||||
| STIG | Date | |||
| SUSE Linux Enterprise Server 12 Security Technical Implementation Guide | 2025-05-14 | |||
Details
Check Text (C-217279r991589_chk)
Note: If the installed version of OpenSSH is 7.4 or above, this requirement is not applicable.
Verify the SUSE operating system SSH daemon performs compression after a user successfully authenticates.
Check that the SSH daemon performs compression after a user successfully authenticates with the following command:
# sudo grep -i compression /etc/ssh/sshd_config
Compression delayed
If the "Compression" keyword is set to "yes", is missing, or the returned line is commented out, this is a finding.
Fix Text (F-18505r880924_fix)
Configure the SUSE operating system SSH daemon performs compression after a user successfully authenticates.
Uncomment the "Compression" keyword in "/etc/ssh/sshd_config" on the system and set the value to "delayed" or "no":
Compression no