VoIPshield

VoIPshield Finds Flaws With Microsoft UC

VoIPshield, a VoIP security solutions company based in Ottawa, Canada, recently discovered vulnerabilities affecting the RTP (Real-time Transport Protocol), a standard data format used for delivery of audio and instant messaging packets over the Internet. Microsoft Office Communications Server 2007, Microsoft Office Communicator, and Microsoft Windows Live Messenger.

This excerpt from the VoIPshield press release explains the issue further:  “Most of the attention in enterprise VoIP/UC security has been paid to the control channel, where SIP and other signalling protocols are used,” said Ken Kousky, CEO of security research and analysis firm IP3 and advisor to the VoIP Lab at Illinois Institute of Technology. “Until now, the media stream has been largely ignored by the security community as a source of malicious activity.  But attacks from these vectors have the potential to be dangerously persistent and widespread.”

There are an estimated 250 million computers running at least one of these applications. If exploited, the discovered vulnerabilities could result in a DoS (denial-of-service) attack that impacts not just the affected application, but the entire computer system. VoIPshield’s research and disclosure are specific to the Microsoft products mentioned, but they note that these same protocols are used elsewhere and that other VoIP and communications applications are likely impacted by similar vulnerabilities in the media delivery channel.

Risk of RTP ‘Monoculture’

One of the issues or stumbling blocks facing organizations as they adopt unified communications is the interoperability (or lack thereof) between systems. A company would like to know that the platform they invest in will be able to integrate, or at least cooperate with, disparate platforms being used by vendors, customers, or future merger and acquisition targets.

In the world of VoIP (Voice over IP), there is a more or less agreed upon standard in RTP (Real-Time Transport Protocol). That is great for universal interoperability, but some have suggested that it may also pose a security risk for VoIP networks. The potential ‘monoculture’ of RTP could mean that any successful exploit against the protocol could cripple not one VoIP platform, but all VoIP platforms simultaneously.

I do agree that organizations need to be concerned with VoIP and unified communications security, but I believe that the ‘RTP monoculture’ issue is primarily FUD being used to sell VoIP security solutions from the vendors claiming the sky is falling. The thing is that monoculture is largely a myth. The ‘Microsoft monoculture’ was just anti-Microsoft FUD.

Each organization has different perimeter security, different products and applications inside the network, different security policies and controls across their environments. Yes, they may all use RTP, but everything else about their network and VoIP configuration is unique to each organization. Hopefully, if they have done their homework and put the right kinds of security controls in place, an RTP exploit that impacts one company won’t necessarily impact them.