UCF STIG Viewer Logo

AIX must turn off TCP forwarding for the SSH daemon.


Overview

Finding ID Version Rule ID IA Controls Severity
V-215301 AIX7-00-002118 SV-215301r508663_rule Medium
Description
SSH TCP connection forwarding provides a mechanism to establish TCP connections proxied by the SSH server. This function can provide similar convenience to a Virtual Private Network (VPN) with the similar risk of providing a path to circumvent firewalls and network ACLs.
STIG Date
IBM AIX 7.x Security Technical Implementation Guide 2022-06-06

Details

Check Text ( C-16499r294354_chk )
If TCP forwarding is approved for use by the ISSO, this is not applicable.

Check the SSH daemon configuration for the "AllowTcpForwarding" directive using command:

# grep -i AllowTcpForwarding /etc/ssh/sshd_config | grep -v '^#'
AllowTcpForwarding no

If the setting is not present or the setting is "yes", this is a finding.
Fix Text (F-16497r294355_fix)
Edit the "/etc/sshd/sshd_config" file to add the following line and save the change:
AllowTcpForwarding no

Restart the SSH daemon:
# stopsrc -s sshd
# startsrc -s sshd