Researchers ‘break’ Edge with zero-day remote code exploit

Security researchers have teased a zero-day exploit for Microsoft's Edge browser that can allow a malicious actor to run commands on a user's machine.

Two vulnerabilities, discovered by exploit developer Yushi Laing with help from Alexander Kochkov, could allow an anonymous user execute code remotely, and potentially seize control of a user's device.

Laing teased the "stable exploit" for the Microsoft-developed web browser last week with an image that appeared to show the Windows Calculator app launched from a web browser, after working on the project for just under a week.

The researcher had initially been looking into three remote code execution bugs for Firefox as part of an 'exploit chain', but struggled to establish code for the third. He then found two similar flaws on Microsoft Edge using the Wadi Fuzzer app developed by SensePost.

Laing told BleepingComputer the pair wanted to develop a stable exploit for Microsoft Edge and escape the sandbox, termed as an exploit that force-crashes and incorrectly reloads an app with manipulated permissions.

This would allow a user to run functions, and access other apps, beyond its normal permissions, as well as access data from other applications. They were also looking for a way to effectively seize control of a machine by escalating execution privileges to 'system'.

They published a proof-of-concept for the Edge exploit in a short clip which shows the team using the browser to open the landing page for Google Chrome via Firefox.

Microsoft previously left a zero-day Edge exploit unpatched for 90 days, which led to Google's Project Zero security team publishing the full details.

The flaw was nowhere near as severe as a remote code execution bug, rather it allowed an attacker who had already seized control of a browser to bypass a second layer of security.

Laing said the pair will not go public with their latest Edge exploit until they finalise their write-up.

"Microsoft has a strong commitment to security and a demonstrated track record of investigating and providing resolution as soon as possible," Microsoft's senior director Jeff Jones told IT Pro.