Trojan:HTML/Browlock is ransomware that prevents users from accessing the infected machine's Desktop; it then demands payment, supposedly for either possession of illegal material or usage of illegal software.
Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.
A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:
Check for the latest database updates
First check if your F-Secure security program is using the latest detection database updates, then try scanning the file again.
Submit a sample
After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.
NOTE If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.
Exclude a file from further scanning
If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.
Note You need administrative rights to change the settings.
Trojan:HTML/Browlock has been reported to target users in multiple countries, including the United States, the United Kingdom and Canada. Typically, it will display a 'lock screen' purportedly from a local or federal law enforcement authority, claiming that the machine has been locked and encrypted due to 'illegal activities'. A 'fine' is then demanded to restore the system.
This malware was also covered in our Labs Weblog blogpost:
A lock screen used by one Browlock variant is shown below: