Petya ransomware removal and system recovery (upd. Dec. 2017)

Learn how the Petya ransomware is different from other crypto threats, why it is considered a high-profile infection, and how to go about the attack.

The ransomware called Petya illustrates the fact that crypto viruses are evolving over time. The perpetrators are no longer content with the tactic where victims’ personal data is held for ransom, although that’s a highly effective extortion mechanism per se. The threat actors are gradually beginning to focus on denying the accessibility of the whole operating system instead. This, beyond doubt, is a more unfavorable scenario for infected users, because they don’t even get the chance to try forensic instruments and thus revive some of the locked files. Petya overwrites the Master Boot Record of a contaminated system and then encrypts the master file table so that the user is unable to even boot into Windows. To sort things out, the victim is told to send $300 worth of Bitcoin (0.13 BTC) to a specific wallet address.

The latest variant of this plague catalogued as Petya.A started running rampant on June 27, 2017. This massive outbreak first hit multiple organizations in Ukraine, including the IT infrastructure of the country’s Government. The high-profile Ukrainian targets include private and state-owned banks, postal services, telco providers, energy companies, retail companies, and even TV media holdings. Later on, victims from Spain, France and Russia started reporting the same incidents, with the geography of the attacks continuously expanding. According to security analysts’ preliminary verdicts, the new Petya ransomware spinoff wreaking havoc in Ukraine appears to engage some bluff in its extortion activity. It locks computers – that’s true, but no data gets encrypted for real in the course of the attack.

When the corrupt loader finds itself on a computer, it displays a User Access Control dialog box in order to try and obtain administrator privileges. Interestingly enough, in case the user clicks No on the UAC popup, the attack will discontinue, so there is quite a bit of social engineering involved here. The newer edition of this ransomware, though, is bundled with a Trojan called Mischa, which comes into play if the original infection fails to dupe the victim into granting it the permissions.

In the event this part of the brainwashing succeeds, Petya forces the target computer to reboot. Once Windows has restarted, the ransomware displays a fake CHKDSK scan (says, “Repairing file system on C:”) to distract the victims from what’s going on in the background. Meanwhile, it is modifying the MBR, which is a fragment of data located at the beginning of the hard disk. The virus also implements the so-called Salsa10 stream cipher to scramble the MFT. Given the damage, it’s critical to prevent the OS from rebooting in between the phases above, otherwise the troubleshooting beyond paying the ransom becomes nearly impossible.

Then, Petya ransomware displays a warning screen that says,

Ooops, your important files are encrypted.
If you see this text, then your files are no longer accessible, because they have been encrypted. Perhaps you are busy looking for a way to recover your files, but don’t waste your time. Nobody can recover your files without our decryption service.
We guarantee that you can recover all your files safely and easily. All you need to do is submit the payment and purchase the decryption key.

In order to get hold of the key mentioned in the alert message, the user must submit a Bitcoin equivalent of $300 to a specified Bitcoin wallet address. After the payment has been completed, the victim has to send their Bitcoin wallet ID and “personal installation key” (mentioned in the warning screen) to the following email address: wowsmith123456@posteo.net.

As it has been mentioned above, the ransom amounts to $300, which is currently worth 0.13 BTC. Its size doubles if the victim fails to pay up during 7 days – the countdown is displayed on the Tor-hosted Petya decryption site for each user individually. To avoid the worst-case scenario when dealing with the Petya ransomware, it’s recommended to follow a number of tips. First of all, do not download email attachments that look fishy. Also, do not click any links embedded in spam emails and refrain from loading suspicious files on associated cloud services. A crucial precaution is to decline the User Account Control request described above.

Petya ransomware manual removal and file recovery

If already infected, try the following first:

1. Download LiveCD and create bootable rescue media (CD or USB);
2. Then restart your computer and boot from the device you just created. If the rescue CD goes with TestDisk feature, be sure to run it as it may get your system to operate.
3. The next move is to eliminate Petya ransomware proper, including every temp file it left behind – a reliable security suite will do the trick.

This workaround is definitely not a panacea, but any options are worthwhile in a predicament like that. The ransom route should be the last resort rather than the first thing on the agenda. See below for more details.

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 data 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.

Ransomware Prevention Tips

To avoid Petya ransomware and other file-encrypting infections in the future, follow several simple recommendations:

These techniques are certainly not a cure-all, but they will add an extra layer of ransomware protection to your security setup.

Petya ransomware automated removal and data recovery

When faced with ransomware like Petya, one of the best shortcuts in terms of removal is to use Combo Cleaner, a lightweight and incredibly effective application with PC security and optimization features under the hood. It detects and thoroughly deletes threats while giving you insights into the overall health of your computer.

This program’s protection power spans modules that forestall all known types of malware, including ransomware and browser hijackers, and take your online security to the next level by blocking phishing sites and other suspicious web pages. Follow these simple steps to eliminate the infection for good:

1. Download Combo Cleaner installer.

Download Petya remover

^{Combo Cleaner scans your PC with no strings attached, but you’ll have to buy its fully functional version to remove the threats it detects. The disk optimization tools that find large files and duplicates are free to use.}

2. Open the CCSetup.exe file to get started. Several subsequent screens will allow you to make initial customizations so that the program works exactly as you need from the get-go.

3. The installation will be followed by an update of malware signatures. Once this process is through, click the Start Scan button in the left-hand sidebar.

4. Combo Cleaner will then check system locations that are most often polluted by Windows malware. The first scan can take a while to finish.

5. Combo Cleaner will display a system tray notification as soon as the scan is over. Click the Resolve found threats button to view the results.

6. The scan summary shows the names and types of the detected threats as well as their statuses and locations. Click the Remove all threats button and follow further on-screen prompts to get rid of these items.

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 Stellar Data Recovery features this type of a capability and therefore it can be applied in ransom attack scenarios to at least get the most important files back. So use the app to get an idea of what data can be restored and let it do the recovery job. Here is a step-by-step walkthrough:

1. Download and install Stellar Data Recovery.

Download Stellar Data Recovery

2. Open the application, select the types of recoverable files to look for, and click Next.

3. Choose the areas you want the tool to recover from and click the Scan button.

4. Having scanned the specified locations, the program will display a notification about the total amount of recoverable data. Close the dialog and click the Recover button. This will hopefully help you get some of your valuable files back.

Petya 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 Petya 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.

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 data 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.

Ransomware Prevention Tips

To avoid Petya ransomware and other file-encrypting infections in the future, follow several simple recommendations:

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. Another benefit of using the antimalware tool is that it will keep ransomware threats from intruding on your computer further on.

Download Petya removal tool