The recent emergence of the cryptovirus called Fantom evokes some nontrivial contemplations. The first portion of food for thought is whether educational ransomware initiatives are more useful than harmful. Another consideration has to do with the extent to which users should trust the very look and feel of commonplace system processes, such as critical updates. Extensive analysis of the above-mentioned ransomware sample provides answers to these serious questions.
With an abundance of file-encrypting malware breeds circulating on the open Internet these days, it’s becoming harder to tell one sample from another. They all seem to go the same route of scrambling a victim’s files, displaying a recovery roadmap, and then extorting money for the data. And yet, the devs of the Fantom ransomware have managed to break out of the routine box in several ways. This pesky specimen obscures the workflow of data encryption on a targeted computer by forcibly overlaying the current set of all user interfaces with a fake critical Windows update screen. It looks true-to-life because it’s identical to the genuine counterpart and even displays the progress status of the rogue update. One more way in which the attackers benefit from this contrivance is that it doesn’t raise red flags for the user in terms of the spike of CPU consumption during file encoding, which is a normal occurrence for regular system maintenance.
It turns out that Fantom ransomware is one of the tens of EDA2 spinoffs propagating in the wild. EDA2 is a proof-of-concept designed by Turkish malware analyst named Utku Sen. The researcher wrote the code for this educational ransomware and ventured into posting it on GitHub so that everyone interested could test. At that point, it was within the realms of possibility that this POC could be abused by actual cybercriminals. To evade the worst-case scenario, Mr. Sen embedded a backdoor into the code, which was supposed to crack any real ransom Trojan based on it. Now, the makers of Fantom were able to eliminate this deliberate flaw and thus didn’t have to build the infection from scratch.
Going back to the compromise workflow, Fantom ransomware finds and encrypts all the widespread types of files on the infected PC. The cryptographic algorithm it uses is AES-128, which leverages the same key for the encryption and decryption routines. Some unprofessionally devised offending programs of this sort attach this secret key to their executables, which has allowed experts to create multiple free decryptors. With Fantom, though, this isn’t the case. The 128-bit key doesn’t actually touch the contaminated computer – instead, it is retrieved directly from the C2 server only for the time span necessary for scrambling the data. That’s a smart move of the extortionists.
The infection concatenates the .fantom extension to all the ciphered files. It also spawns copies of the DECRYPT_YOUR_FILES.html document all over the system, including the desktop and the affected directories with data. This file tells the victim to send an email to email@example.com or firstname.lastname@example.org with their ID that’s indicated in the ransom note. Then, the crooks will get back to the person with further decryption steps. The recovery involves a buyout of the AES key, where the ransom is somewhere in the range of 0.5-1 Bitcoin. Luckily, a number of forensic methods may enable the affected user to restore some ransomed files for free. Be sure to try them if infected.
Fantom ransomware automatic removal
Extermination of this ransomware can be efficiently accomplished with reliable security software. Sticking to the automatic cleanup technique ensures that all components of the infection get thoroughly wiped from your system.
1. Download recommended security utility and get your PC checked for malicious objects by selecting the Start Computer Scan option
2. The scan will come up with a list of detected items. Click Fix Threats to get the ransomware and related infections removed from your system. Completing this phase of the cleanup process is most likely to lead to complete eradication of the plague proper. Now you are facing a bigger challenge – try and get your data back.
Methods to restore files encrypted by Fantom ransomware
Workaround 1: Use file recovery software
It’s important to know that the Fantom ransomware creates copies of your files and encrypts them. In the meanwhile, the original files get deleted. There are applications out there that can restore the removed data. You can utilize tools like Stellar Data Recovery for this purpose. The newest version of the ransomware under consideration tends to apply secure deletion with several overwrites, but in any case this method is worth a try.
Workaround 2: Make use of backups
First and foremost, this is a great way of recovering your files. It’s only applicable, though, if you have been backing up the information stored on your machine. If so, do not fail to benefit from your forethought.
Workaround 3: Use Shadow Volume Copies
In case you didn’t know, the operating system creates so-called Shadow Volume Copies of every file as long as System Restore is activated on the computer. As restore points are created at specified intervals, snapshots of files as they appear at that moment are generated as well. Be advised this method does not ensure the recovery of the latest versions of your files. It’s certainly worth a shot though. This workflow is doable in two ways: manually and through the use of an automatic solution. Let’s first take a look at the manual process.
Use the Previous Versions feature
The Windows OS provides a built-in option of recovering previous versions of files. It can also be applied to folders. Just right-click on a file or folder, select Properties and hit the tab named Previous Versions. Within the versions area, you will see the list of backed up copies of the file / folder, with the respective time and date indication. Select the latest entry and click Copy if you wish to restore the object to a new location that you can specify. If you click the Restore button, the item will be restored to its original location.
Apply Shadow Explorer tool
This workflow allows restoring previous versions of files and folders in an automatic mode rather than by hand. To do this, download and install the Shadow Explorer application. After you run it, select the drive name and the date that the file versions were created. Right-click on the folder or file of interest and select the Export option. Then simply specify the location to which the data should be restored.
Verify whether Fantom ransomware has been completely removed
Again, ransomware removal alone does not lead to the decryption of your personal files. The data restore methods highlighted above may or may not do the trick, but the ransomware itself does not belong inside your computer. Incidentally, it often comes with other ransomware, which is why it definitely makes sense to repeatedly scan the system with automatic security software in order to make sure no harmful remnants of this ransomware and associated threats are left inside Windows Registry and other locations.