Every VoIP assessment should follow a list of specific checks in order to give the client the necessary security assurance about his VoIP infrastructure. A checklist also disallows the pentester of forgetting to execute specific tests and therefore it prevents incomplete assessments.
After years of conducting this type of test I have compiled a list of attacks in a specific order of execution that I perform in every engagement.
- VoIP-001 – VLAN hopping from data network to voice network
- VoIP-002 – Extension Enumeration & Number Harvesting
- VoIP-003 – Capturing SIP Authentication
- VoIP-004 – Eavesdropping Calls
- VoIP-005 – CallerID spoofing
- VoIP-006 – RTP injection
- VoIP-007 – Signaling Manipulation
- VoIP-008 – Identification of insecure services
- VoIP-009 – Testing for Default Credentials
- VoIP-010 – Application level vulnerabilities
- VoIP-011 – Voice Mail Attacks
- VoIP-012 – Phone Firmware Analysis
You can find the list also on my GitHub account.
If you execute on your VoIP assessments more attacks please reply with a comment and I will update the list accordingly.