A very well concealed and effective ransomware has been reported to encrypt user files with the .rokku file extension. It is known as Rokku Ransomware, and its malicious files have a very low detection rate by antivirus software. Users who have been affected and have had their files encrypted by Rokku’s strong cypher are strongly advised not to pay any ransom money to the cyber-criminals for file decryption. Instead, experts warn that the ransomware should immediately be removed and alternative file restoration methods, such as the ones illustrated in this article, to be sought after.
|Short Description||Encrypts the data on the infected computer and demands a ransom payment (in BitCoin or other services) from the user for its restoration.|
|Symptoms||The user’s files are encrypted with an added .rokku file extension to them.|
|Distribution Method||Via malicious URLs or email attachments.|
|Detection Tool||Download Malware Removal Tool, to See If Your System Has Been Affected by Rokku|
|User Experience||Join our forum to discuss Rokku.|
|Data Recovery Tool||Windows Data Recovery by Stellar Phoenix Notice! This product scans your drive sectors to recover lost files and it may not recover 100% of the encrypted files, but only few of them, depending on the situation and whether or not you have reformatted your drive.|
Rokku Ransomware – Spread
To be distributed throughout the user PCs, the ransomware may use the most modern file obfuscators and a Trojan.Downloader or an Exploit Kit. It may look for the most desirable targets to spam malicious URLs containing the Trojan or the Exploit kit. This means that you may encounter it in several websites where it is likely that you may have clicked on an infected URL.
But this is not the only mean of distribution, ransomware such as Rokku uses to spread. It may also be distributed in malicious URLs or (less likely) malicious attachments featured in spam emails. The attachments may be archives since most e-mail service providers have the ability to block the attachments from potentially dangerous emails.
Once an activation has been initiated a port may be opened on the compromised computer and the actual Rokku ransomware payload may be downloaded on the victim’s PC.
Rokku Ransomware In Detail
Once this cryptomalware has been initiated on your device it may begin to deploy its malicious modules to several different Windows locations:
- %User’s Profile%
The files may be of several executable formats (.vbs, .tmp, .bat, .dll, .exe) and they may have different functions.
The ransomware then scans for the most used file extensions by the user which may be the commonly used file extensions(http://fileinfo.com/filetypes/common) and encrypts them putting the .rokku file extension on them. An encrypted file may look like the following:
→ DSC008.jpg.rokku without an icon
After encoding the user data, the crypto-malware places the following files for the user to see:
The files are essentially ransom notes of this malware, which contain the instructions for the user to read and hopefully for the cyber crooks pay ransom money to decrypt the files via an anonymous Onion-based network. Here are the contents of the ransom notes:
→ “YOUR FILE HAS BEEN LOCKED
To unlock your files, follow the instructions bellow:
1. Download and install Tor Browser
2. After a successful installation, run Tor Browser and wait for its initialization.
3. Type in the address bar: http://z092uue92j2eks2m.onion
4. Follow the instructions on the site.”
Remove Rokku Ransomware and Restore Your Files
Regarding the removal of this ransomware, one must be very careful and perform a backup of the encrypted data on an external drive or in the cloud. Then it is advisable NOT to reinstall Windows. Instead, it is recommended to use advanced anti-malware software to detect all of its associated files plus other malware that may currently be residing on your computer.
Regarding the file restoration, it is preferable if you will attempt to decrypt directly the data to use a powerful computer. In case you are trying to bypass direct decryption and attempt methods like file restoration, it is crucial not to format the HDD from your computer. More information and methods you may find in step “4. Restore files encrypted by Rokku” below.