Vulnerability patched: Grammarly’s Chrome extension is secure once again

Grammarly, the ever-popular grammar tool provider, has patched a cybersecurity vulnerability in its Chrome extension. Currently used by 22 million people, the bug allowed for unauthorised access to private user files.

Tavis Ormandy, the researcher from Google’s Project Zero, is the man who discovered it. He believes it’s of high severity, since it exposed authentication tokens to all websites.

Looking at the report, the extension unwillingly exposed a user’s history, logs, documents, and other data to any website.

Ormandy labelled the cybersecurity vulnerability as a severe violation of user expectations, since granting any website you visit the ability to snoop inside the personal documents you’ve sent to another website is not something most users tend to be comfortable with.

To solidify his point, the researcher presented a proof-of-concept code. Examining it reveals the fact that it was possible to take advantage of the bug with nothing more than four simple lines of code.

He reported the bug on Friday. Typically, there is a 90-day disclosure deadline, but the company was quick to respond, and the patch has been available since Monday. There’s no need to do anything on your part as it’s an automated update.

This is not the only browser plugin that found itself under Ormandy’s scrutiny. In the recent months, he has checked several of them, with Cisco WebEx Chrome extension and LastPass being two of the freshest examples. The former contained a remote code execution flaw, while the latter had a data-stealing bug.