After malicious actors started adapting their techniques, Google has decided to ban the installation of extensions for the Chrome web browser from sources other than the Chrome Web Store.
Google announced in November 2013 plans to protect Windows users against malicious extensions by requiring all extensions to be hosted on the Chrome Web Store. The company started enforcing this policy in May 2014 and the results have been positive — customer support help requests for uninstalling unwanted extensions dropped 75%.
The policy was not enforced on the Windows developer channel of Chrome to give developers more freedom when testing their applications. This might have been beneficial for developers, but cybercriminals have also used it to their advantage.
According to the search giant, malicious actors have been tricking Windows users into using the developer channel of Chrome in order to install extensions that were not hosted in the official web store.
That is why Google has decided to enforce the policy for all channels, including the OS X version, starting with July 2015. The policy has already been enforced on all Windows channels of Chrome this week, and OS X will follow soon.
“For developers, we’ll continue to support local extension installs during development as well as installs via Enterprise policy. To provide an integrated install flow from your own website, you can make use of the existing inline installation feature,” Jake Leichtling, Extensions Platform Product Manager at Google, wrote in a blog post.
“The extension platform unlocks powerful features that can help users get the most out of Chrome. However, it is crucial that our users stay safe from the reaches of malicious software developers. Extending this protection is one more step to ensure that users of Chrome can enjoy all the web has to offer without the need to worry as they browse,” Leichtling noted.
While most of the extensions hosted on the Chrome Web Store are safe, malicious applications have been known to get through Google’s verification process. Just last month, experts spotted a suspicious third-party extension that had been downloaded 1.2 million times from the web store. The extension, Webpage Screenshot, uploaded users’ browser data to a remote server.
A recent study conducted by Google and researchers at University of California, Berkeley on the ad injection economy revealed the existence of 50,000 browser extensions that took control of browsers and injected advertisements. As part of the same study, researchers discovered 192 deceptive extensions that affected 14 million users on the Chrome Web Store.