Haha, I had spent a considerable amount of time responding to and finding hijacks due to this issue. After trying different scripts and tools, I believe bbot is

Haha, I had spent a considerable amount of time responding to and finding hijacks due to this issue. After trying different scripts and tools, I believe bbot is the best tool to find these issues [1]. I am always complaining about how Azure knows what IPs, domains, tradfficmanager,etc... you have, it should validate this before letting other customers reuse them. That said, there are difficult scenarios like: hn.com -> cname hn.westeurope.cloudapp.azure.whatever -> vm IP. The problem that's hard for azure to fix is when you get rid of the VM and/or azure domain, azure doesn't know that your domain (hn.com in the exmaple) is using their domain as cname since you would use your own nameservers. I could enumerate hn.com, find out that a cname record in azure is nxdomain and grab/hijack it. There are many ways such hijacks can happen. Highly recommend auditing your domains with bbot (which also finds loads if other issues). [1] https://github.com/blacklanternsecurity/bbot https://github.com/blacklanternsecurity/bbot