.CTBL File Extension

CTB-Locker Ransomware Encrypted File

Developer N/A
2.0  |  1 Vote
Category Encoded Files
Format N/A

What is a CTBL file?

A file with a .ctbl extension is a file that has been encrypted by CTB-Locker ransomware. It is encrypted with advanced elliptic-curve cryptography (ECC), which means that you cannot change the .ctbl file extension to open it.

More Information

CTB-Locker ransomware is a type of malware similar to the Cryptolocker and Cryptowall (.AAA) virus utilized by cybercriminals. It first surfaced in July 2014, and is a ransomware-as-a-service (RaaS) offering, which cybercriminals can purchase to deploy attacks. It may attack all types of users but primarily targets the web servers of organizations based in the USA, Italy, Germany, and the Netherlands.

How did my computer get infected?

The ransomware is typically distributed via malicious email attachments in the form of Word .DOCX, .DOC, and .DOCM files, or another type of executable file. When you download and open a file attachment the CTB-Locker virus runs on your computer. To prevent attacks like these, never open email messages from unverified senders.

What does the CTB-Locker ransomware do to my files?

Once introduced to your computer, the ransomware takes your files hostage by encrypting them and adding the .ctbl extension onto the names of your files. Any type of file may be encrypted, such as spreadsheets, videos, pictures, and documents. For example, a spreadsheet.xlsx file becomes spreadsheet.xlsx.ctbl or spreadsheet.xlsx.CTBL.

The virus then generates a DecryptAllFiles.txt file in every folder that stores an infected file, an AllFilesAreLocked.bmp image, an .HTML file. These files are ransom notes that provide information explaining the hostile takeover of your files and how you can recover your files by paying a ransom, typically in Bitcoin.

How to open a CTBL file

Unfortunately, you cannot open CTBL files without a CTB-Locker decryptor tool. Currently, there is no decryptor available to effectively restore infected files.

If you have a recent backup of your files, you can perform a System Restore to remove the virus, but any changes made to files after the backup was created will be lost.


FileInfo.com recommends you never pay a ransom to decrypt files encrypted by ransomware. Paying a ransom encourages ransomware distributors to continue their efforts, and there is no guarantee that paying a ransom will give you access to your files. Instead, you should restore your data from a recent backup created before the ransomware infected your computer.

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Programs that open CTBL files

System Restore
Updated April 2, 2021

Verified by FileInfo.com

The FileInfo.com team has independently researched the CTB-Locker Ransomware Encrypted file format and Windows apps listed on this page. Our goal is 100% accuracy and we only publish information about file types that we have verified.

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