iaxflood

iaxflood is designed to perform denial-of-service attacks on VoIP servers, specifically targeting Asterisk IP PBX systems using the IAX protocol. A UDP IAX packet captured from an IAX channel between two Asterisk PBXs serves as the payload source for the flood attack. This approach requires more processing from the target PBX compared to a simple udpflood without IAX-like payload, even if the IAX protocol header does not perfectly match the target.

Use cases include testing the resilience of VoIP infrastructure against flood attacks and demonstrating vulnerabilities in Asterisk-based systems. The tool floods a specified destination from a source IP by sending a defined number of packets to port 4569, the default IAX port.

It is particularly effective because the crafted IAX payload mimics legitimate traffic, potentially bypassing basic flood protections while still consuming significant resources on the target PBX.

iaxflood sends UDP packets containing a captured IAX payload to the target destination on port 4569 from the specified source IP and same source port. The tool sets the IP_HDRINCL socket option to include IP headers in the packets. While the IAX protocol header may not match the target Asterisk PBX exactly, the payload requires additional processing, amplifying the impact beyond a generic UDP flood. The number of packets is user-specified, enabling controlled flood intensity.