Knowledge Base

Becoming one of the biggest threats in the digital world, ransomware can target anyone from individuals to large corporations. In this article, we will cover all the details in detail, such as what ransomware is, how to protect yourself, and what steps to take if it gets infected.

What is Ransomware?

Ransomware is malicious software that encrypts files on a computer or server and demands a ransom from the user to be able to decrypt these files.

How Does It Work?

• Infects the computer through a malicious file or link.

• Encrypts all important files on the system.

• Leaves a ransom note (mostly saved on the desktop or in folders).

• Demands payment in Bitcoin or similar cryptocurrencies to decrypt the files.

Common Ransomware Types:

• CryptoLocker

• WannaCry

• Locky

• Ryuk

• Conti

How to Get Hit by a Ransomware Attack?

• Phishing emails (fake invoice, fake shipping information)

• Fake software updates

• Using stolen RDP (Remote Desktop) credentials

• Malware spreading over the network

• USB sticks and portable disks

Symptoms Observed on a Ransomware-Infected Computer

• Changing file extensions (such as .locked, .crypt, .encrypted)

• File names turning into random characters

• Leaving notes such as "HOW_TO_DECRYPT.txt" on the desktop or in folders

• The system slowing down a lot

• Corruption of normal working files and applications

First Things to Do on Ransomware-Infected Systems

1. Immediately Disconnect the Network Connection

   • Turn off Wi-Fi or Ethernet connection.

   • Because ransomware can spread to other devices within the network.

2. Turn Off the Device

   • If intervened before the encryption process is completed, some files may be recoverable.

3. Do Not Pay the Ransom

   • Even if you pay, there is no guarantee that the files will be returned.

   • In addition, they may continue to target you as a "payer".

4. Get Professional Support

   • Consult cybersecurity experts or data recovery companies.

How to Solve Changed File Extensions?

1. Use Decryptors

• Free decryption tools are available for some ransomware types.

• Sample resources:

  • No More Ransom Project (https://www.nomoreransom.org/)

  • Emsisoft Decryptors

2. Restore from Backup

• The most definitive solution is to restore the system or data from a secure backup.

3. Try File Recovery Tools

• Some software (Recuva, Disk Drill) can recover unencrypted old file remnants.

4. Manual Solution Efforts

• If a fixed key is used in some ransomware variants, it can be solved with expert help.

Methods to Protect Against Ransomware

1. Make Regular Backups

• Keep offline and cloud-based backups.

• Store backups on storage devices that are not connected to the network.

2. Use Security Software

• Actively use antivirus and antimalware programs.

• Prefer software with ransomware protection module (Bitdefender, Malwarebytes, etc.).

3. Education and Awareness

• Especially in corporate environments, raise employee awareness with phishing training.

4. Keep Systems Up to Date

• Keep Windows, Linux, applications and all software up to date to close open doors.

5. Use Email and Web Filters

• Use security solutions that detect malicious attachments and links in advance.

6. RDP (Remote Desktop) Security

• Do not leave RDP ports open.

• Provide access via VPN.

• Use encrypted and multi-factor authentication.

Extra Precautions on Ransomware-Infected Servers

• Take a full disk image of the system and copy it to an isolated environment.

• Determine how the attack was carried out by analyzing the system logs (event viewer).

• If the Active Directory structure is affected, consider resetting or reinstalling.

Conclusion

Protection against and response to ransomware attacks is vital for both individual and corporate users. Regular backups, system updates, and conscious internet use have become a necessity for protection.

Remember; the best protection starts with proactive measures!