How To Stop Ghost Calls

How to block unwanted ghost calls

Last updated on May 16th, 2023 at 02:09 pm

When it comes to nuisance calls, ghost calls often sit at the top of the nuisance calls list. The most frustrating thing about ghost calls is the lack of control the recipient of the call has. We’ll talk about what they are, where they come from and how to stop ghost calls.

What are Ghost Calls?

A ghost call happens when the recipient of the call picks up the telephone, yet there is nobody on the other end of the call and the caller does not leave a message.

Ghost calls can occur at any time throughout the day, with the most annoying calls happening in the middle of the night. Ghost calls are virtually untraceable and leave no sign of any numbers.

image of a ghost from blog post titled: How to stop ghost calls

The frustrating part about ghost calls is the sheer fact that there is nothing on the other end of the call other than complete silence. Apart from being very annoying and time-consuming, ghost calls can often leave the recipient of the call anxious and scared.

How to identify a Ghost Call

The calls are typically carried out by doing what is called a “Port scan”, often conducted by companies running automated software, looking to discover devices, which happen to be telephone and mobile phones.

The most reliable way of tracking the original source of ghost calls is by finding the caller ID log. Typically, the ID log will reveal incoming numbers of an unusual pattern. For example, the caller ID usually contains prefixes or codes, with numbers such as 1001, 1000, and 100. These type of telephone numbers typically don’t exist, and if they do show up in call logs, it’s a strong indicator that the call has originated from a “non-existent” source.

Where do Ghost Calls come from?

Ghost calls originate from automated port scanning devices and not from service providers, as some people assume. Random port scans are carried out, with the objective to reveal potential vulnerabilities within the phone system.

The main annoyance with ghost calls is the fact that the call recipient can be billed for accepting calls, whilst the caller remains undetected and free from any charges.

By running SIP scans, hackers can manipulate ports, by testing for the presence of SIP, which stands for (Session Initiation Protocol). If a hacker runs a successful scan, the data can be used to obtain passwords as well as clone the phone system they have targeted, allowing the hackers to make calls that the recipient on the other end, unfortunately, will have to pay for.


How to stop Ghost Calls from a landline

The best way to stop ghost calls from a land line would be to buy either a call blocker or a phone with call blocking built-in.

Cordless Phones such as the BT 4600 Big Button Phone & BT Premium Phone, or corded phones like the BT Decor 2600 come with software built into the phone which can pre-screen the call for you – in other words, they can silently answer the call for you and request that the caller identify themselves before ringing the phone, this way all silent calls are ignored.

A bonus feature is, that for non-ghost calls, the call has still been pre-screened, it will ask the caller to identify themselves verbally and record the caller giving their details – the phone will then ring for the user to pick up and will play back the recording of the caller introducing themselves so you can listen to whom is calling, then have the option of accepting or ignoring the call.

These phones also have whitelists where you can add friendly numbers to the phonebook so family and friends will get straight through, where all other numbers are screened.

You can find a range of cordless telephones with Call Blocking features available on our website.

Reporting Ghost and Scam Calls

If you’re worried about recieving ghost calls or scam calls, get in touch with your call service provider and they should be able to help further – we have listed a number of direct links to provider reporting pages below:


How to stop Ghost Calls from a business cloud or VoIP line

If your VoIP services are hosted by an external company, then the first thing is to notify them immediately as there are things that they can do to help you stop receiving the calls at the exchange side. However if you host and administrate your own system, then there are a few quick things you can look at to help prevent ghost callers.

SIP port change 

Most port scanners wil look at the default ports first making ghost calls more frequent if your SIP phone system is operating on the default port 5060 port. To prevent ghost calls coming through, the phone adapter or SIP port can be changed by the administrator of your phone system from 5060, to any other free port of your chosing. Most ghost calls are run via automated scripts and tools, so if you’re using an obscure port, this should nip a huge percentage of your voice calls in the bud.

Disable direct IP calls

There’s usually a setting within SIP admin panels the admin that allows direct IP to IP calls within the admin panel of your SIP system. If you’re not using IP to IP calling as part of your regular usage, then disabling this should also prevent ghost calls from port scanners who have spotted a SIP system your IP.

Blocking Ghost Calls by using a Firewall

Using a Firewall is a reliable way of blocking ghost calls. You should carefully look at your network traffic and create relevent Black and White lists so that only the traffic you intend should come through to your SIP phone system.

For advanced SIP/VoIP admins – SIP Vicious Pro

If you’re an advanced SIP Admin then you could use a tool like SIP Vicious Pro which is a command line security toolset that allows you to test the security of your SIP system and find the vunerabilities in your own system that could be allowing ghost and scam callers through.


Don’t be haunted by Ghost Calls

If you continue to ignore ghost calls, in the long term, they could potentially end up causing a lot of worry for home users, or costing business a lot of money. It’s important to remain vigilant and react quickly to any ghost calls you receive.

  • Report – Tell your service provider or SIP cloud administrator you’re recieving these calls.
  • Block – Spammers and ghost callers
  • Prevent – Future attacks.
image of a hacker

By remaining proactive, you can plan ahead and avoid the potential annoyance of any ghost calls in the future.