Presented at DEF CON 15 (2007)
Aug. 4, 2007, 8 p.m.
Real-time Transfer Protocol (RTP) is used almost ubiquitously by Voice over IP technologies to provide an audio channel for calls. As such, it provides ample opportunity for creation of a covert communications channel due to it's very nature and use in implementation. While use of steganographic techniques with various audio cover-mediums has been extensively researched, most applications of such have been limited to audio cover-medium of a static nature such as WAV or MP3 file audio data. This presentation details common techniques for use of steganography with audio data cover-medium, outlines the problem issues that arise when attempting to use these techniques to establish a full-duplex communications channel using audio data transmitted via an unreliable streaming protocol, and finally documents solutions to these problems as well as a reference implementation entitled SteganRTP.
- Computer Academic Underground
I)ruid: Founder of the Computer Academic Underground, co-founder of the Austin Hackers Association (AHA!), and currently employed in VoIP Security Research by TippingPoint, a division of 3Com, I)ruid has over a decade of experience in various areas of information security including vulnerability assessment and penetration testing, secure network architecture, and vulnerability research and development, including research in specific areas related to the security of network protocols, network applications, and Voice over IP (VoIP). Over the years I)ruid has been involved with many security community projects such as design and development of SPF for e-mail (RFC 4408) and contributing as a data mangler for the OSVDB. I)ruid has also released numerous tools to the community such as the infamous PageIt! mass-paging tool and the hcraft HTTP exploit-crafting framework. He regularly releases vulnerability and exploit advisories, speaks at security related events and conferences, is on the Technical Advisory Board of the Voice over IP Security Alliance (VoIPSA), is an active participant in various VoIPSA projects, and is a regular contributor to the Voice of VoIPSA blog.