Sigma ransomware fix and data decryption

Learn what kind of a cyber threat the SIGMA RANSOMWARE is and get the hang of the workarounds to remove this destructive program and recover hostage files.

Malicious apps that perform unauthorized encryption of victims’ data and hold it for ransom have been the biggest scourge of the digital world for years. Although their share in the current threat landscape has decreased lately due to the growth of cryptocurrency mining malware, they continue to wreak havoc big time. Speaking of the ransomware called Sigma, it is one of the few competently devised infections from this category that’s sticking around. As opposed to most blackmail infections out there, this one does not change filenames in any way. Neither will they be replaced with random hexadecimal strings, nor will an extra extension be appended to them. What does happen to the targeted files is they become inaccessible so that no regular application can be used to open them.

The Sigma ransomware is all about spam and phishing when it comes to distribution. The perpetrators at the helm of it have been generating massive volumes of spam carrying the masqueraded malicious payloads. The themes of these messages can be related to Craigslist advertising, careers, receipts, invoices and other potentially catchy subjects. What all of these tricky emails have in common is Microsoft Word documents attached to them. When the recipient tries to open the file, it will display a security warning stating that macros have been disabled and recommending the user to turn them on via the ‘Enable Content’ button. Doing so is a big mistake, because that one click is what separates the user from being infected. It triggers an obfuscated VBA script that downloads Sigma ransomware and executes it on the PC.

The next stage of the onslaught is to find all data that’s most likely important to the victim. In order to do it, Sigma runs a surreptitious computer scan and locates all files whose extensions match a predefined list that corresponds to popular types of information. These include various graphics formats, documents, databases, and videos – the types of objects that can usually be flagged ‘personal’. The ransomware then encrypts all the detected files with RSA-2048 cipher and, unfortunately, does it the right way.

When finished, the pest drops ransom notes into folders with locked data, plus a copy on the desktop. These are named ReadMe.txt, and their goal is to inform the victim about what happened to their files and to provide a Tor link leading to the Sigma ransomware payment page. Said resource indicates the size of ransom and the Bitcoin address to send it. The amount is $400 worth of Bitcoin, and it is valid for seven days. After that, the ransom doubles. Essentially, this is the cost of the attackers-owned RSA private key and the alleged decryptor. No one guarantees successful recovery after this payment, though. Crooks aren’t the most trustworthy people to deal with, obviously, so be sure to first try all alternatives available to ransomware victims.

Sigma ransomware automated removal and data recovery

When faced with ransomware like Sigma, 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 Sigma 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.

Sigma 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 Sigma 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 recovery of Sigma-encrypted files

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 Sigma 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 Sigma removal tool