Don't be a VoIP eavesdropping victim

Posted on Wednesday October 31, 2018

In the digital world, eavesdropping is a form of cyberattack where voice over internet protocol (VoIP) phone calls are intercepted and recorded, usually to glean personal or business information. Since it does not affect call quality, it's hard to tell if you've been a victim of eavesdropping. Ensure that you never become one by implementing these security strategies.

Change the default configurations

Using your VoIP phones without changing the default configurations can be the worst mistake you can make. Doing so means bad guys can search vendor documentation for things like default usernames and passwords. Depending on your VoIP solution, you should have the option of changing the default configurations on your VoIP handsets. Otherwise, you should come up with a manual process to change default configurations before rolling phones out to your staff.

Get updates from your handset vendor

In 2015, Cisco detected vulnerabilities in their VoIP phones that enabled attackers to listen in on phone conversations. Cisco quickly issued security alerts, but if they hadn't, several companies would have fallen victim to VoIP eavesdropping. The lesson here is you must regularly monitor advisories from your hardware vendor or work with an IT provider that does so for you. Without proper monitoring, you won't know how susceptible your corporate VoIP phones are to being eavesdropped.

Update session border controllers

Another way to combat VoIP eavesdropping is to constantly update your session border controllers (SBCs). By doing so, you'll be updating your VoIP's antivirus software, so your systems are better protected from constantly evolving cyberthreats. Routine SBC updates are essential for securing SIP trunking as well as responding to new threats.

Encrypt VoIP calls

If you work in a regulated industry like healthcare or finance, encrypting VoIP calls is essential to staying compliant. Work with your VoIP provider and auditors to determine the best encryption options for your communications infrastructure. Many cloud VoIP providers offer call encryption guidelines, and some even offer it as a premium service.

Build a hardened VoIP network

Make sure your VoIP network includes:

• IP private branch exchange (PBX) using minimal services, so that the hardware can only power the PBX software
• Firewalls with access control lists set to include call control information
• Lightweight Directory Access Protocol lookup, and signaling and management protocol
• Reinforced endpoint security with authentication at the endpoint level

To effectively combat VoIP eavesdropping, businesses need to take a holistic approach. This includes policies, deployment, and security practices that will keep malicious agents out of your network. Feel free to contact us for further information on how to protect your business.