Popular Internet browser Mozilla Firefox has caught a fatal security flaw that could allow cybercriminals to hack and delete files on your computer. All of this can happen to you unnoticed.

Taking advantage of this flaw in Firefox, the attackers activate a script on the computer using the browser’s PDF viewer and JavaScript that can search and extract files from your PC’s hard disk. The source of this malicious script has been identified from an ad on a Russian site. Users will be affected by visiting the page of the ad.

One thing to note here is that the script is mainly about the files used by the developers.

Firefox developer Mozilla is a blog In the post The malicious script is currently working on the Firefox browser used in Windows and Linux operating systems. In other words, Firefox users are safe on Apple’s Mac computers for the time being. However, Mozilla has asked all operating system users to be cautious and recommend updating the Firefox browser. If you are using Firefox, you can download Firefox now to version 39.0.3. Get updated. And enterprise customers install the 36.1.1 patch.