Trojan:W32/Cryptowall is a ransomware that silently encrypts files on the user's machine and demands a ransom to provide the decryption key needed to decrypt the files.
F-Secure detects ransomware using a variety of signature and generic detections. Once detected, the F-Secure security product will automatically remove the file.
If the ransomware uses encryption to take files or an entire system hostage, the encryption may be sufficient to make it very difficult to decrypt the files without the necessary decryption key.
In such circumstances, the recommended course of action is to report the crime to the relevant authorities and restore the affected data from a backup.
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.
Cryptowall is ransomware that is reportedly spread in malicious file attachments to email messages; through downloads of malicious programs from compromised sites; and in the payloads of other malware.
When the Cryptowall malware run on a computer, it encrypts files stored on the machine, then displays a message informing the user that a decryption key must be purchased in order to recover access to the files held at ransom. Payment is typically requested in the Bitcoin digital currency.
If you believe you have encountered an undetected Cryptowall sample, please send it to us for analysis via our Submit A Sample (SAS) page.