The SUSE operating system SSH daemon must not allow compression or must only allow compression after successful authentication.

Severity
Group ID
Group Title
Version
Rule ID
Date
STIG Version
mediumV-217279SRG-OS-000480-GPOS-00227SLES-12-030250SV-217279r991589_rule2024-11-253
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.
ℹ️ Check
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
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