The use of VoIP phone systems has surged due to COVID-19: several internet service providers have reported an increase in VoIP usage of between 44 to 88 percent.

As we’ve established at 3CX, the rise in VoIP usage is good news because you can reduce your phone bill by as much as 80 percent by using an IP telephony system.

voip hacking

The bad news, however, is that attempts to hack VoIP phone systems have increased as well: data from RedShift Network shows that enterprise customers experience at least 40,000 different VoIP/SIP attacks on any given day.

If you don’t have strong VoIP security, your IP telephony system might have been compromised.

Here are three signs that your VoIP system has been hacked:

1. A sudden increase in phone bills

You should pay significantly less when using VoIP, not more.

If, for whatever reason, you suddenly notice your VoIP bills going up significantly without any corresponding change in the calls you’ve been making, you’ve most likely been hacked.

While this might not look like a big deal, it is: there have been cases in which companies racked up as much as 34 years worth of VoIP bills in a weekend due to being hacked.

2. Unknown numbers in VoIP call history

Performing regular audits of your call history is one of the main ways to quickly discover if you’ve been compromised: if you begin to notice calls to strange numbers, particularly internationally, you should pay careful attention. If these strange calls become more frequent, you’ve most likely been hacked.

3. A significant increase in the number of weekend and off-hour calls

You know you rarely use your VoIP system on weekends or during off-hours but all of a sudden start seeing signs of calls being made on your VoIP phone system around that time. There’s only one explanation: you’ve been hacked.

Protecting Your VoIP Phone System

You can secure your VoIP system by:

  • Enabling your VoIP’s anti-hacking feature (3CX has a built-in anti-hacking feature).
  • Using strong and secure passwords for both your IP phones and administrative interface.
  • Using a firewall to restrict traffic from non-trusted networks.
  • Hardening your operating system to prevent unnecessary services.
  • Regularly upgrade your OS and VoIP phone firmware (3CX’s makes this easy with its firmware upgrade feature).

Bamidele Onibalusi is a Google-certified digital marketer and an Hubspot-certified freelance writer with passion for the tech industry. You can follow him on Twitter: @youngprepro.