Get exhaustive information on CryptoLocker replica called the PClock ransomware, including its background, distribution vectors and extortion methodology.
PClock is one of the few present-day ransomware samples whose timeline goes back to early 2015. What is more, its look and feel has hardly changed over time. It is one of the numerous copycats of the ill-famed CryptoLocker strain. Whereas the original edition of PClock targeted a little over 100 file types, the currently active variant zeroes in on more than 2,600 formats of data stored on victims’ computers. A major tweak of its modus operandi that occurred around November 2016 also brought about a new propagation tactic. The ransom Trojan is now planted on systems by means of Crimace, a malware downloader that’s effectively a Nullsoft Scriptable Install System package. The payload mostly arrives with an email pretending to contain a fax. The attached password-protected archive may be named “Criminal Case against _You-[random string].rar”.
As soon as an unsuspecting recipient opens the RAR object, they are required to enter a password indicated right in the body of the message. This is most likely a trick aimed at preventing antimalware suites from raising red flags on the attachment. Instead of opening the purported fax, the user unknowingly launches a Windows Script File (.WSF) which, in its turn, fires up the infection chain. Although the above-mentioned Crimace Trojan then generates an error popup saying that the fax cannot be displayed, the ensuing PClock trespass takes place in the background. The ransomware scans the computer’s hard disk and network drives for a bevy of file types and encrypts them. Note that the filenames stay the same, with no extra extension being appended to them. They simply become inaccessible due to the strong crypto. This routine is followed by the display of a warning window titled “CryptoLocker” that reads, “Your personal files are encrypted!”
The interactive edition of PClock ransom note allows the victim to select their preferred language and view a complete list of affected data by clicking the “Show files” button at the bottom. An embedded countdown timer puts additional pressure on the plagued user, urging him or her to pay up within 120 hours, otherwise the private decryption key will supposedly be destroyed. This is bluff, though, as the deadline usually extends further, perhaps with a bigger size of the ransom. The original amount is 0.55 Bitcoin, which is worth about $570 at this point.
PClock also drops several plaintext copies of its data decryption how-to’s on the desktop. These documents are called “Your files are locked !.txt”, with the number of exclamation marks for different editions reaching five. The ransomware also drops the following files: CryptoLocker.lnk, en_files.txt, and en_gfiles.txt. The first one is a desktop shortcut for accessing the main PClock window, and the other two hold the list of enciphered files. In the latest wave of attacks, the ransom Trojan instructs victims to contact the threat actors via firstname.lastname@example.org or email@example.com, though the email addresses listed in the ransom manuals may also be firstname.lastname@example.org or email@example.com. Although there is currently no free decryptor for the current version of PClock, the tips and tricks below may help retrieve data without having to meet the perpetrators’ demands.
PClock ransomware automated removal and data recovery
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.
PClock 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 PClock 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 PClock 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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