The SSH client must not permit tunnels.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
|---|---|---|---|---|
| V-39270 | GEN005532-ESXI5-709 | SV-51086r3_rule | Medium |
| Description |
|---|
| OpenSSH has the ability to create network tunnels (layer-2 and layer-3) over an SSH connection. 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 |
|---|---|
| VMware ESXi Server 5.0 Security Technical Implementation Guide | 2017-01-06 |
Details
| Check Text ( C-46534r8_chk ) |
|---|
| Disable lock down mode. Enable the ESXi Shell. Execute the following command(s): # grep Tunnel /etc/ssh/ssh_config If the "Tunnel" attribute is not set to "no", this is a finding. If the /etc/ssh/ssh_config file does not exist or the Tunnel option is not set, this is not a finding. Re-enable lock down mode. |
| Fix Text (F-44249r7_fix) |
|---|
| Disable lock down mode. Enable the ESXi Shell. Execute the following command(s): # vi /etc/ssh/ssh_config Add/modify the attribute line entry to the following (quotes for emphasis only): "Tunnel no" Re-enable lock down mode. |