Blocking AzureCloud due to malicious traffic

I haven’t posted in a long time but I felt the need to mention this to anyone else who might need to consider it. There has been a significant uptick in malicious traffic to my website over the last few months and I decided to do some analysis of from where it is coming. A huge source of these probes (looking through logs there are hundreds and hundreds of 404s that seem to be looking for vulnerable software) are Microsoft IP addresses. Digging around, it turns out they seem to be Azure VPS instances. I opened tickets with Microsoft at https://cert.microsoft.com for several of these IP addresses but the tickets were closed within a minute with a generic response: “This report could not be validated, no action was taken.”

It seems others have had this same issue.

Since this is a personal website and I don’t really need to be concerned with corporate connectivity, I decided just to block the entire AzureCloud. You can conveniently download the list from here in JSON format. I blocked the AzureCloud network prefixes.

Good bye, Azure VPS.