The ESXi host Secure Shell (SSH) daemon must be configured to not allow X11 forwarding.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| medium | V-256392 | SRG-OS-000480-VMM-002000 | ESXI-70-000023 | SV-256392r959010_rule | 2025-02-11 | 1 |
| Description |
|---|
| X11 forwarding over SSH allows for the secure remote execution of X11-based applications. This feature can increase the attack surface of an SSH connection. |
| ℹ️ Check |
|---|
| From an ESXi shell, run the following command: # /usr/lib/vmware/openssh/bin/sshd -T|grep x11forwarding Expected result: x11forwarding no If the output does not match the expected result, this is a finding. |
| ✔️ Fix |
|---|
| From an ESXi shell, add or correct the following line in "/etc/ssh/sshd_config": X11Forwarding no |