Electronic Arts has fixed a vulnerability in its online gaming platform Origin after security researchers found they could trick an unsuspecting gamer into remotely running malicious code on their computer.

The bug affected Windows users with the Origin app installed. Tens of millions of gamers use the Origin app to buy, access and download games. To make it easier to access an individual game’s store from the web, the client has its own URL scheme that allows gamers to open the app and load a game from a web page by clicking a link with origin:// in the address.

But two security researchers, Daley Bee and Dominik Penner of Underdog Security, found that the app could be tricked into running any app on the victim’s computer.

“An attacker could’ve ran anything they wanted,” Bee told TechCrunch.

The researchers gave TechCrunch proof-of-concept code to test the bug for ourselves. The code allowed any app to run at the same level of privileges as the logged-in user. In this case, the researchers popped open the Windows calculator — the go-to app for hackers to show they can run code remotely on an affected computer.

But worse, a hacker could send malicious PowerShell commands, an in-built app often used by attackers to download additional malicious components and install ransomware.

Bee said a malicious link could be sent as an email or listed on a webpage, but could also be triggered if the malicious code was combined with a cross-site scripting exploit that ran automatically in the browser.

It was also possible to steal a user’s account access token using a single line of code, allowing a hacker to gain access to a user’s account without needing their password.

Origin’s macOS client wasn’t affected by the bug.

EA spokesperson John Reseburg confirmed a fix was rolled out Monday. TechCrunch confirmed the code no longer worked following the update.