Despite the impossibility to get around the encryption algorithm used by Crypt0L0cker ransomware, the infected users are not necessarily doomed to pay up.
Computer crime has made a sweeping move towards the conceptual framework where end users are bound to buy services sold by the black hat actors on this arena. File encrypting malware is what demonstrates this drastic change, literally compelling its victims to submit money so they can regain access to the things that belong to them in the first place. It targets one’s personal files, treating this sort of data as low hanging fruit in disgusting cyber blackmailing schemes. The name of one such program, Crypt0L0cker, reflects its effect based on distorting the order of 1s and 0s on the contaminated hard disk. Given its tech features and a number of unique infrastructural markers, this infection is believed to be a descendant of the TorrentLocker virus that vanished from the malicious software scene months ago.
Most of the time, Crypt0L0cker will not end up inside a Windows machine unless the user inadvertently commits an action that triggers the bad routine. The scammers in charge have been running a massive phishing campaign, sending out emails that are disguised as legal notices, delivery tracking details, CVs, payrolls and the like. The peril lurks in the attachments to these messages, which can look like PDF documents or ZIP archives. As soon as the user clicks on this file, the ransomware gets inconspicuously dropped in the system and instantly downloads the components it needs for deploying the extortion. While scanning the HDD, mapped drives and removal hardware, which is what the trojan does at the beginning of the attack, it detects all files that are likely to be important to the user. Interestingly, Crypt0L0cker has a file exclusions list, unlike most ransomware specimens out there. It therefore skips the items that are required for normal operation of the system.
In the meantime, the ‘right’ files get encrypted with asymmetric algorithm, where the private key is mandatory for decryption along with the paired public key. Since the former isn’t stored on the PC, it is essentially the main object of manipulation. In order to get it, the user has to pay 2.2 Bitcoins. The respective directions are all provided in a file named DECRYPT_INSTRUCTIONS, which is available in HTML and TXT formats. By adding a system.pif file to the startup preset, the virus makes this document automatically open right after the computer is booted up. The entirety of communication with the malicious C2 server is tunneled via The Onion Router, so it’s hard for the law enforcement agencies to monitor this traffic. The infected people are also being pressured by a deadline to pay the money, which is 96 hours, otherwise the sum will be increased.
In the event you’ve been attacked by this vicious malware, be sure to make some attempts to restore the files before surrendering to what the criminals want. To this end, review the part below and try the steps listed.
Automated removal of Crypt0L0cker ransomware
Owing to an up-to-date database of malware signatures and intelligent behavioral detection, the recommended software can quickly locate the infection, eradicate it and remediate all harmful changes. So go ahead and do the following:
1. Download and install the antimalware tool. Open the solution and have it check your PC for PUPs and other types of malicious software by clicking the Start Computer Scan button
2. Rest assured the scan report will list all items that may harm your operating system. Select the detected entries and click Fix Threats to get the troubleshooting completed.
Data recovery toolkit to the rescue
Some strains of ransomware are known to delete the original files after the encryption routine has been completed. As hostile as this activity appears, it can play into your hands. There are applications designed to revive the information that was obliterated because of malfunctioning hardware or due to accidental removal. The tool called Data Recovery Pro by ParetoLogic features this type of capability therefore it can be applied in ransom attack scenarios to at least get the most important files back. So download and install the program, run a scan and let it do its job.
Crypt0L0cker ransomware manual removal and file recovery
Some ransomware strains terminate themselves after completing the encryption job on a computer, but some don’t. Furthermore, the Crypt0L0cker virus may prevent victims from using popular antimalware tools in order to stay on board for as long as possible. Under the circumstances, it may be necessary to utilize the Safe Mode with Networking or System Restore functionality.
- Restart the machine. When the system begins loading back up, keep pressing the F8 key with short intervals. The Windows Advanced Options Menu (Advanced Boot Options) screen will appear.
- Use arrow keys to select Safe Mode with Networking and hit Enter. Log on with the user account infected by the ransomware.
- Click on the Search icon next to the Start menu button. Type msconfig in the search field and select the System Configuration option in the results. Go to the Boot tab in the upper part of the GUI.
- Under Boot options, select Safe boot and click the Apply button. A prompt will appear to reboot the computer so that the changes take effect. Select the Restart option and wait for the system to load into Safe Mode. Again, log on with the ransomware-stricken user account.
In Safe Mode, the ransom Trojan won’t keep security software from running or otherwise thwart troubleshooting. Open your preferred web browser, download and install an antimalware tool of choice and start a full system scan. Have all the detected ransomware components removed in a hassle-free way.
- Open Windows Advanced Options Menu as described in the previous section: hit F8 repeatedly when the PC is starting up. Use arrow keys to highlight the Safe Mode with Command Prompt entry. Hit Enter.
- In the Command Prompt window, type cd restore and hit Enter
- Type rstrui.exe in the new command line and press Enter
- When the System Restore screen pops up, click Next, select a restore point that predates the contamination, and use the application’s controls to roll back the system to this earlier state.
Be advised that even after the ransomware is removed, files will still be encrypted and inaccessible. The malicious code cleanup part, however, is important because it keeps a relapse of the infection from occurring further on and eliminates all opportunistic malware.
Ways of non-ransom file recovery
Cracking the crypto used by this ransom Trojan is more of a science fiction thing rather than an attainable prospect for the masses. This is why the troubleshooting in predicaments of this sort is a matter of two approaches: one is to pay the ransom, which isn’t an option for many victims; and the other is to apply instruments that take advantage of the ransomware’s possible weaknesses. If the latter is your pick, the advice below is a must-try.
Checking one’s options regarding this workaround is doable in two ways: through the Properties menu of each file or by means of the remarkable open-source tool called Shadow Explorer. We recommend the software-based way because it’s automated, hence faster and easier. Just install the app and use its intuitive controls to get previous versions of the encrypted objects reinstated.
Alternatively, you can leverage the Previous Versions feature, which is native to Windows operating system. This method is more cumbersome that the use of ShadowExplorer, but it can help restore the most important individual files on condition that the ransomware failed to disable the Volume Snapshot Service on the computer. Right-click on a file of choice and select Properties. Then, go to the Previous Versions tab as illustrated below.
Go ahead and pick the file’s latest backup version on the list. Use the Copy or Restore buttons to reinstate this object to a new path or to its original folder, respectively.
Ransomware Prevention Tips
To avoid Crypt0L0cker ransomware and other file-encrypting infections in the future, follow several simple recommendations:
- Toggle your email provider’s anti-spam settings to filter out all the potentially harmful incoming messages. Raising the bar beyond the default protection is an important countermeasure for ransom Trojans.
- Define specific file extension restrictions in your email system. Make sure that attachments with the following extensions are blacklisted: .js, .vbs, .docm, .hta, .exe, .cmd, .scr, and .bat. Also, treat ZIP archives in received messages with extreme caution.
- Rename the vssadmin.exe process so that ransomware is unable to obliterate all Shadow Volume Copies of your files in one shot.
- Keep your Firewall active at all times. It can prevent crypto ransomware from communicating with its C&C server. This way, the threat won’t be able to obtain cryptographic keys and lock your files.
- Back up your files regularly, at least the most important ones. This recommendation is self-explanatory. A ransomware attack isn’t an issue as long as you keep unaffected copies of your data in a safe place.
- Use an effective antimalware suite. There are security tools that identify ransomware-specific behavior and block the infection before it can do any harm.
These techniques are certainly not a cure-all, but they will add an extra layer of ransomware protection to your security setup.
Revise your security status
Post-factum assessment of the accuracy component in malware removal scenarios is a great habit that prevents the comeback of harmful code or replication of its unattended fractions. Make sure you are good to go by running an additional safety checkup.
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