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

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-22488	GEN005539	SV-26787r1_rule	ECSC-1	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
SOLARIS 9 X86 SECURITY TECHNICAL IMPLEMENTATION GUIDE	2015-10-01

Details

Check Text ( C-27790r1_chk )
Check the SSH daemon configuration for the Compression setting. # grep -i Compression /etc/ssh/sshd_config | grep -v '^#' If the setting is not present, or set to yes, this is a finding.

Fix Text (F-24036r1_fix)
Edit the SSH daemon configuration and add or edit the Compression setting value to no or delayed.