Enlarge / No, no you can’t. (credit: Nathan Mattise)

Google’s App Engine may not have been designed to provide a way for developers to evade censors, but for the past few years it has offered one, via a technique known as domain fronting. By wrapping communications to a service with a request to an otherwise innocuous domain or IP address range such as Google’s, application developers can conceal requests to domains otherwise blocked by state or corporate censors. It’s a method that has been used both for good and ill—adopted by Signal, the anti-Chinese censorship service GreatFire.org, plugins for the Tor anonymizing network, some virtual private network providers, and by an alleged Russian state-funded malware campaign to obfuscate Tor-based data theft.

But on April 13, members of the Tor Project noticed that domain fronting had become broken. The reason, according to a report by The Verge’s Russell Brandom, is that Google made changes to the company’s network architecture that had been in the works for some time. A Google representative told Brandom that domain fronting had never been officially supported by Google, and it only worked until last week “because of a quirk of our software stack… as part of a planned software update, domain fronting no longer works. We don’t have any plans to offer it as a feature.”

Ars attempted to contact Google, but we’ve received no response as of press time.