Trojan:JS/Agent is a very large family of trojans written in JavaScript.
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.
Agent trojans often arrive via a surreptitious drive-by download, when a file is silently dropped onto a computer or device during a visit to a malicious (or legitimate but compromised) website.
Alternatively, the trojans may be dropped and installed as part of the payload of another program, usually other malware.
Once installed on the system, the malicious actions performed vary depending on the specific Agent variant. Some Agent variants may perform data-harvesting functions, while others install other malware onto the system.
For a representative example of a variant in the Trojan:JS/Agent family, see the following description: