If you use Firefox, you should update right away

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A woman looks at her mobile phone as she stands in front of a poster of Mozilla Firefox on February 27, 2013 at the Mobile World Congress, the world's biggest mobile fair, in Barcelona. The European Union warned member states on February 26 to free up the airwaves for new, super-fast fourth generation mobile networks and threatened legal action against those that deliberately block the process. AFP PHOTO/JOSEP LAGO (Photo credit should read JOSEP LAGO/AFP/Getty Images)
Photograph by Josep Lago — AFP/Getty Images

If you use Firefox, you could be at risk because of a flaw in the software that could be used to steal files from your computer.

In a blog post published Thursday, Mozilla explained: “A Firefox user informed us that an advertisement on a news site in Russia was serving a Firefox exploit that searched for sensitive files and uploaded them to a server that appears to be in Ukraine.”

“The vulnerability comes from the interaction of the mechanism that enforces JavaScript context separation (the “same origin policy”) and Firefox’s PDF Viewer,” Mozilla said. “Products that don’t contain the PDF Viewer, such as Firefox for Android, are not vulnerable,” the post continued.

Not to worry though, as Mozilla has already released an update to fix the problem.