VoIP systems vulnerable to identity theft

VoIP calls could be intercepted by criminals and hackers. They need to be encrypted

The majority of VoIP telephone systems are vulnerable to interception and hacking attacks. That's the view of Phil Zimmerman, the creator of Pretty Good Privacy (PGP), who believes that VoIP technologies now need to be encrypted.

"We must encrypt VoIP because it's vulnerable," he said in an interview published in PC Answers magazine. "On the public switched telephone network (PSTN), the government could easily wiretap [a call] and criminals could not. With VoIP anyone can wiretap."

VoIP vulnerability

Zimmerman goes on to explain how a VoIP hack might work if your computer, or one of the computers on a local network, was infected with spyware that could monitor all IP traffic. This spyware would sniff for unencrypted VoIP traffic and then record it to the computer's hard disc as WAV files. There's a utility that already does it here.

"Someone on the other side of the world who put that spyware there could browse through those files and selectively play the interesting ones - without even coming into your country."

It's a hacking strategy that hasn't been possible before via the existing telephone network. While PC-to-PC calls on Skype already employs 256-bit AES encryption, the rest of the VoIP industy isn't so well protected. It's a glaring gap that Zimmerman aims to fill with Zfone, an end-point encryption application for SIP/RTP that he's developed. Think of it as PGP for VoIP.

"VoIP is a growth industry and it needs to be encrypted," adds Zimmerman. "Criminal organisations will start attacking VoIP as soon as it becomes big enough to attract them."

Zfone is currently available as a beta release and can be downloaded from the Zfone website. The full interview with Phil Zimmerman appears in the October 2007 issue of PC Answers, out now.

Latest in Computing
best of Studio Ghibli movies Netflix
I refuse to jump on ChatGPT’s Studio Ghibli image generator bandwagon because it goes against everything I love about those movies
Lenovo Legion 5i
It's the best time to buy an RTX 4070 gaming laptop since Black Friday - get up to $600 off on massive clearance deals
Three angles of the Apple MacBook Air 15-inch M4 laptop above a desk
Apple MacBook Air 15-inch (M4) review roundup – should you buy Apple's new lightweight laptop?
Computer memory RAM on motherboard background
How to enable XMP
David Kampf #64 of the Toronto Maple Leafs warms-up before playing the Philadelphia Flyers at the Scotiabank Arena on March 25, 2025 in Toronto, Ontario, Canada.
ChatGPT and Gemini Deep Research helped me choose an NHL team to support, and now I'm obsessed with ice hockey
Person printing
Microsoft’s latest Windows 11 update exorcises possessed printers that spewed out pages of random characters
Latest in News
Nintendo Switch 2 Joy-Con up-close from app store
Nintendo's new app gave us another look at the Switch 2, and there's something different with the Joy-Con
cheap Nintendo Switch game deals sales
Nintendo didn't anticipate that Mario Kart 8 Deluxe was 'going to be the juggernaut' for the Nintendo Switch when it was ported to the console, according to former employees
Toni Collette in Hereditary
Everything leaving Netflix in April 2025 – from the scariest movie ever made to a beloved DreamWorks animation with 99% on Rotten Tomatoes
Three angles of the Apple MacBook Air 15-inch M4 laptop above a desk
Apple MacBook Air 15-inch (M4) review roundup – should you buy Apple's new lightweight laptop?
Witchbrook
Witchbrook, the life-sim I've been waiting years for, finally has a release window and it's sooner than you think
Close up of Leica M11-P viewfinder
I wince at the prospect of the rumored Leica M11-V – here's why