Details

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.

Solution

From an SSH session connected to the ESXi host, or from the ESXi shell, add or correct the following line in ‘/etc/ssh/sshd_config’:

PermitTunnel no

Supportive Information

The following resource is also helpful.

• https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_VMW_vSphere_6-5_Y21M10_STIG.zip

This security hardening control applies to the following category of controls within NIST 800-53: Configuration Management.This control applies to the following type of system Unix.

References

• 800-53|CM-6b.
• CAT|II
• CCI|CCI-000366
• Rule-ID|SV-207626r388482_rule
• STIG-ID|ESXI-65-000025
• STIG-Legacy|SV-104083
• STIG-Legacy|V-93997
• Vuln-ID|V-207626

Source

• Tenable.com/audits