Trojan-Downloader:OSX/Flashback is a family of malicious applications which when installed on a computer will download a payload from a remote site, then modify targeted webpages displayed in the web browser. Variants in the Flashback family may include additional malicious functionalities or characteristics.
Disinfection instructions for Flashback malware differ depending on the specific variant present on the machine. Please refer to the individual descriptions for each detected variant (see theTechnical Details section below) for specific removal instructions.
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.
Early Flashback variants disguised themselves as Flash Player installers in order to trick users into installing and executing them.
Subsequent Flashback variants no longer use social engineering tactics to ensure distribution; instead, they are dropped by malicious Java applets exploiting known vulnerabilities, thereby requiring no user action for infection to occur.
Additional technical details are available in the following Labs technical paper: Flashback OS X Malware (PDF)
For more information, please see the individual descriptions for the variants detected:
This malware family is also further discussed in the following Labs Weblog posts: