Chapter 13: Signaling and Media Manipulation

Wow my wife is upset with me. It seems like every time I call her, she gets mad and hangs up on me. I get the cold shoulder all night. She says she knows what is going on and keeps hearing a woman in my office when I call her from my phone. Maybe someone else's conversation is bleeding into my calls. It has been this way ever since we got these new VoIP phones. I talked to the network administrator, but he doesn't seem to like me I wonder if he is up to something???
A frustrated user who is the target of an RTP audio mixing attack

Overview

In the previous chapters, we covered several forms of service disruption in which malformed packets or packet floods disrupted service for SIP proxies and SIP phones. In this chapter, we cover other attacks in which an attacker manipulates SIP signaling or media to hijack or otherwise manipulate calls. As with other attacks we have covered, these attacks are simple to execute and quite lethal.

We used the same SIP test bed as used for Chapter 12, "Flood-based Disruption of Service." Please refer to Figure 12-2 in that chapter's introduction for an illustration of this test bed.