> For the complete documentation index, see [llms.txt](https://www.netexec.wiki/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.netexec.wiki/vnc-protocol/authentication.md).

# Authentication

## Testing credentials

VNC servers may support password authentication, though this is uncommon. Currently, NetExec does not support username auth and will omit any value provided to `--username/-u`.

```bash
nxc vnc <ip> -u '' -p <password>
```

Expected Results:

```bash
nxc vnc 192.168.56.22 -u '' -p 'badpassword'
VNC         192.168.56.22   5900   192.168.56.22    [*] RFB 3.8
VNC         192.168.56.22   5900   192.168.56.22    [+] badpassword
```

## Unauthenticated access

When the VNC server doesn't require authentication, the following output can be expected.

```bash
nxc vnc 192.168.56.22
VNC         192.168.56.22   5900   192.168.56.22    [*] RFB 3.8 (No Auth:True)
```

## Specify port

```bash
nxc vnc 192.168.56.22 --port 5901
VNC         192.168.56.22   5901   192.168.56.22    [*] RFB 3.8 (No Auth:True)
```

## VNC sleep

Increase the VNC socket connection sleep interval to prevent rate limiting.

```bash
nxc vnc <ip> --vnc-sleep <seconds>
```