Google Chrome launches new feature to block Spectre attacks
The next update to Google Chrome will bring new protections against web browser attacks such as Spectre.
Malware running through a website could use attacks such as Spectre to steal data or login information from any website tabs open in a browser.
Google site isolator Charlie Reis says that Spectre’s attack methods are particularly damaging to web browsers.
While major browsers have put some protections in place to protect against speculative execution side-channel attacks, Chrome is taking those protections one step further.
“We believe the most effective mitigation is offered by approaches like Site Isolation, which try to avoid having data worth stealing in the same process, even if a Spectre attack occurs,” Reis says.
Chrome 67 for Windows, Mac, Linux, and Chrome OS will feature what Google calls ‘site isolation’- essentially this means that different tabs open in the browser each have their own ‘rendering’ processes.
Although site isolation has been available as an optional enterprise policy since Chrome 63, numerous bug fixes and improvements have enabled Google to roll the feature out to everyone.
Google is also investigating how to extend site isolation to its Chrome for Android browser. It expects to roll out an experimental enterprise policy for site isolation in Chrome 68 for Android.
Previously Google Chrome used a ‘multi-process architecture’ where different tabs could use different renderer processes, but Reis says there was still potential for attacks.
“However, it was still possible for an attacker's page to share a process with a victim's page. For example, cross-site iframes and cross-site pop-ups typically stayed in the same process as the page that created them. This would allow a successful Spectre attack to read data (e.g., cookies, passwords, etc.) belonging to other frames or pop-ups in its process.”
Reis says site isolation will allow each renderer process will contain documents from a maximum of one site.
“This means all navigations to cross-site documents cause a tab to switch processes. It also means all cross-site iframes are put into a different process than their parent frame, using ‘out-of-process iframes’.”
While it is a major change to Chrome’s behaviour, Reis says that users shouldn’t see any visible changes beyond a few known issues.
It will result in slightly higher memory usage (10-13%) due to the number of running processes, but Reis says Google is committed to optimising speed and security.