​Google gets stricter about HTTPS

Google has started to roll out HTTP Strict Transport Security (HSTS) to prevent people from accidentally using the insecure version of Google's URLs.

Google’s implementation of HSTS will automatically switch insecure HTTP URLs to HTTPS, where a connection between browser and website is encrypted.

HTTPS can prevent an attacker from nabbing a connection to say, a banking website or web email account, and re-directing the user to a bogus page designed to capture passwords. HSTS takes it up a notch by protecting against attacks that attempt to strip encryption from communications with a server.

A website's HSTS policy can also prevent users from accidentally using a non-secure URL even when a secure version exists, which can be done by manually typing in the HTTP URL in the address bar or by opening a HTTP link from other sites.

Google has steadily been moving more of its services to HTTPS since making Gmail encrypted by default in 2014. Today, on average just over 80 percent of requests to Google’s servers use encrypted connections for products spanning Google News, Drive, Maps and Finance.

Chrome, Firefox, Opera, Safari and Internet Explorer support HSTS, and many of the browsers include Chrome’s preload list for sites that have developed an HSTS policy.

Security expert Troy Hunt recently detailed his experience of implementing HSTS within Chromium for his breach notification site Have I Been Pwned. As he noted, while some porn sites had enabled HSTS, none of Australia’s big four banks, nor any major US banks, had done the same.

Jay Brown, a senior technical program manager for security at Google, said the HSTS rollout at Google wasn’t simple.

“Ordinarily, implementing HSTS is a relatively basic process. However, due to Google's particular complexities, we needed to do some extra prep work that most other domains wouldn't have needed to do. For example, we had to address mixed content, bad HREFs, redirects to HTTP, and other issues like updating legacy services which could cause problems for users as they try to access our core domain,” Brown noted.

Besides offering better protection against man-in-the-middle attacks, HSTS also blocks mixed content, which occurs when an HTTPS site loads content from elsewhere over HTTP.

Brown said HSTS was now on for www.google.com however that it is still working on how to minimise the chances that an initial request to its domains happen over HTTP. This first request is vulnerable to a snooping attack.