Trojan-dropper:JS/PdfDropper identifies specially-crafted PDF files that drop and execute a document file. The dropped document file in turn contains code that downloads and runs additional harmful programs.
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.
The PdfDropper file is usually distributed in spam email campaigns. Its appearance and content is usually designed to lure unsuspecting users into opening the file. The PDF file is specially crafted to contain and deliver a document file, which in turn has malicious macro code embedded in it.
Opening the PDF file causes JavaScript code included in it to run, which drops and opens the document file. This executes the embedded macro code, which contacts a remote server to download and run other harmful programs on the machine.
In previously analyzed samples, the downloaded programs include ransomware (Locky) and banking trojans (Dridex).