VoIP Fraud: Protecting Your Business Phone Networks

VoIP fraud is on the rise. Businesses need to understand the threats and how they can mitigate the risk to their voice networks.

VoIP fraud

VoIP has revolutionised business phone networks, in terms of cost, scalability and functionality, bringing all sorts of new benefits to companies that understand the importance of voice communication for business. Which is just one reason why the uptake of VoIP solutions is still rising – VoIP and video conferencing grew 212% during the pandemic – and as legacy copper-based PSTN networks begin to be phased out, more companies are making the move.

However, when any data is transmitted over the internet, there are security risks. For IP-based business voice networks, that can mean VoIP fraud, leading to financial loss, operational failures, compliance failure and reputational damage. So, it’s vital that voice network security becomes an important part of every company’s security infrastructure.


VoIP: a security blind spot

Information security systems and technologies have undergone massive change over the years, developing from the basic ports and protocols stateful firewalls of the early noughties into advanced next-generation firewalls with application and user awareness, along with other advanced threat prevention countermeasures.

Modern security systems now provide extensive layers of protection at both the application layer as well as the network layer. Despite this however, voice communications still remain a blind spot for the vast majority of leading security vendors, with most solutions lacking the kind of application-specific countermeasures required to properly protect modern, IP-based communications systems from common types of attack.


Types of VoIP fraud

VoIP systems can be compromised by malware, network intrusions and DDoS attacks, as well as fraud and nuisance calls. Attacks on business voice networks are becoming more frequent and more sophisticated. In a report published in 2023, 85% of those surveyed said it was time to elevate voice as a threat vector.

VoIP fraud often occurs in conjunction with other types of scams and attacks such as identity theft, phishing and system hacking. Understanding the types of VoIP fraud that occur can help organisations develop systems and protocols to mitigate risk:

VoIP Hacking:

  • Unauthorised Use and Toll Fraud: Hackers manipulate business phone systems to make calls without authorisation. These can be international calls, or to premium numbers, resulting in significant costs.
  • Caller ID Spoofing: Manipulating caller ID information to deceive recipients and impersonate trusted entities.
  • Eavesdropping: Intercepting and monitoring VoIP calls, often by exploiting weaknesses in encryption or network security.
  • Social Engineering: Tricking individuals into revealing sensitive information, through phishing and vishing, or gain access to voice networks, leading to financial loss and identity theft.


SIP (Session Initiation Protocol) Attacks:

SIP trunks connect a company’s PBX (Private Branch Exchange) to the internet for the purpose of managing VoIP sessions. Common attack techniques include:

  • Hijacking: Unauthorised access to SIP endpoints to make phone calls.
  • Server Impersonation: Pretending to be a legitimate SIP server.
  • Message Tampering: Altering SIP message bodies to disrupt communications.


DDoS Attacks:

Distributed Denial of Service (DDoS) attacks disrupt voice networks by overwhelming them with traffic, potentially rendering phones systems unusable. The result is loss of business continuity and potential reputational damage.

Timely detection and preventive measures are crucial to safeguard against voice network fraud. Implementing security protocols, monitoring traffic, and staying informed about emerging threats are essential steps for protecting your business from these risks. However, the good news is that there are now security solutions being developed to address VoIP fraud and other challenges facing business voice networks.


Mitigating VoIP fraud and voice network risk

Any data that travels over the internet is a security risk, and voice data is no different. It can be particularly challenging for companies that rely on contact centres in their operations.

Up until now, companies have relied on traditional firewalls to safeguard digital phone networks, but as voice solutions become more sophisticated so too have the techniques cybercriminals use to infiltrate those systems. And, as well as hacking, fraud, system misuse and nuisance callers, companies have regulatory challenges and compliance rules to navigate. Any solution that can deal with both is a welcome addition to security infrastructure.

Which is why we’re seeing new solutions specifically designed to tackle VoIP fraud, protect voice systems from hackers and help organisations deal with data privacy and compliance legislation.

Most include firewalls to block authorised access to VoIP traffic and VPNs to secure communication channels. But for optimal protection, VoIP traffic should be fully encrypted with MFA (multi-factor authentication) access and control mechanisms. SIP trunks should also be secured with traffic filtering to ensure only legitimate connections.

DigitalWell’s latest security offering, siprotect, comes with all of this, plus added features to protect contact centre operations and assist with compliance. siprotect is an end-to-end solution designed to protect every element of your organisation’s business phone systems, regardless of where you operate, or the PBX system you use.

Look out for our upcoming series of articles examining some of the threats business voice networks face in more detail. In the meantime, you can find out more about siprotect here, or by contacting a DigitalWell representative.