Prevent Nuisance calls - Yealink W52p IP Phone

A number of Yealink users have reported getting frequent nuisance or 'ghost' calls from 1000, 1001 or similar three & four digit numbers. On answering the calls the line appears to be dead with no one at the other end. This seems to be more prevalent among users that are using BT home broadband.

What is causing this issue?

These nuisance calls are due to automated port scanning tools, used by hackers looking for PBX systems to break into. If you are a Deskphone customer do not be alarmed by this, your phones and systems are secure and the hackers are unable to gain access to your phone or our systems, however we understand that the calls are a nuisance. For users of other systems it's recommended to get this resolved as swiftly as possible particularly if you have an on site PBX.

How can I get this to stop? 

In order to get this to stop you will have to follow the following steps; (as always, if you require assistance with this please contact us and we will be happy to guide you through it).

1. Log onto your phone

Firstly we are going to have to get the IP address of your phone. The easiest way to get this information for your W52p cordless IP phone is by pressing the menu button and scrolling to the information 'i' menu item. This will bring up the status of your phone including it's IP address. 

Your IP address should be formatted as follows; 192.168.XX.XXX

Open a browser and type this IP address into the address bar

This will bring up a username and password dialogue box. Enter the default Yealink username and password in here (see below). If you are a Deskphone customer contact support for your unique password.

2. Upgrade to the latest firmware

Make sure your phone is using the latest firmware (V73 - UK  25.73.23.7) - click here to download 

3. Download your Local Config file

WEB UI path:

Phone (top menu)->Configuration (left sub-menu)

Under 'Local Configuration' click Export. This will export a file similar to the below;

000000000000-local.cfg - where 000 is your phones MAC address. 

3. Edit your Local Config Files

Open your local config file created in step 2 with a text editor. It should look something like this;

Add the following lines to the bottom of the file and save.

account.1.sip_trust_ctrl=1
account.2.sip_trust_ctrl=1
account.3.sip_trust_ctrl=1
account.4.sip_trust_ctrl=1
account.5.sip_trust_ctrl=1
features.direct_ip_call_enable = 0

Your new local config file should look something like this;

Notes:

account.X.sip_trust_ctrl=1 - Enables the IP phone to only accept the SIP message from the SIP and outbound proxy server. 1-5 is for each of the accounts on the W52p

features.direct_ip_call_enable = 0 - Enables the phone to be dialled by an IP address directly.

4. Import your new config file

Now that you have an edited local config file this will need to be imported back into the phone for those setting changes to take effect. 

WEB UI path:

Phone (top menu)->Configuration (left sub-menu)

Under 'Local Configuration' select the newly edited config file and click Import. 

You will want to reboot your base station for the changes to be implemented this can be done by power cycling the unit (pulling out the power cord and re-inserting).

That's it, if the steps above have been followed correctly you should no longer receive nuisance or ghost calls to your phone.

Note: Please be very careful not to change any of the other settings in the phones web UI. Changing certain settings may cause the phone to stop working especially within the account settings pane.

As always if you require any additional help please contact us at support@desk-phone.com or call us on 02034342068.