Microsoft obtained a court order allowing it to take over various domains owned by free dynamic DNS provider "No-IP" [1]. According to a statement from Microsoft, this was done to disrupt several botnets [2] . However, No-IP is crying foul, stating that Microsoft never contacted them to have the malicious domains blocked. Further, Microsoft is apparently not able to properly filter and support all queries for these seized domains, causing widespread disruption among legit no-ip customers. According to the court order, Microsoft is able to take over DNS for the affected domains, but because the legit domains far outnumber the malicious domains, Microsoft is only allowed to block requests for malicious domains.

Microsoft apparently overestimated the abilities of it's Azure cloud service to deal with these requests.

In the past, various networks blocked dynamic IP providers, and dynamic IP services have been abused by criminals for about as long as they exist. However, No-IP had an abuse handling system in place and took down malicious domains in the past. The real question is if No-IP's abuse handling worked "as advertised" or if No-IP ignored take down requests. I have yet to find the details to that in the law suit (it is pretty long...) and I am not sure what measure Microsoft used to proof that No-IP was negligent.

For example, a similar justification may be used to filter services like Amazon's (or Microsoft's?) cloud services which are often used to serve malware [4][5]. It should make users relying on these services think twice about the business continuity implications of legal actions against other customers of the same cloud service. There is also no clear established SLA for abuse handling, or what level of criminal activity constitutes abuse.

[1] http://www.noticeoflawsuit.com
[2] http://blogs.technet.com/b/microsoft_blog/archive/2014/06/30/microsoft-takes-on-global-cybercrime-epidemic-in-tenth-malware-disruption.aspx
[3] http://www.noip.com/blog/2014/06/30/ips-formal-statement-microsoft-takedown/?utm_source=email&utm_medium=notice&utm_campaign=takedown
[4] http://blog.malwarebytes.org/fraud-scam/2014/04/cyber-criminals-interested-in-microsoft-azure-too/
[5] http://www.washingtonpost.com/blogs/the-switch/wp/2014/01/16/amazon-is-a-hornets-nest-of-malware/

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Johannes B. Ullrich, Ph.D.
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