Trojan.JS.Likejack is JavaScript malware that silently trickes the user into clicking a 'Like' button for a Facebook page without their knowledge or authorization.
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 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.JS.Likejack is essentially a form of 'clickjacking', in which an attacker uses HTML or coding trickery to disguise a 'Like' button or tag and place it on a page in such a way that the user is lured into unintentionally clicking it. For example, this can be done by placing a transparent button over a link and asking the user to click the link, thus inadvertently also clicking the button. By doing so, the attacker can fraudulently gain 'Likes'; with enough 'Likes', the attacker can then distribute other fake or malicious content.
Trojan.JS.Likejack is often distributed in fake or compromised webpages and in malicious videos spread on forums or social media.
In late November 2014, this malware was reportedly found being used in videos posted on Facebook that were related to a premium car giveaway scam.