Cdtt Virus Ransomware (.cdtt File)

What is Cdtt ransomware?

Cdtt ransomware is a virus that is worth being afraid of. It encrypts your files and asks for a ransom, and also crushes several vital system elements. Struggling to open certain web pages, inability to make the But the knowledge of who is your enemy is 50% of the wind upon this enemy.

The Salsa20 encryption algorithm, which is used by ransomware, is almost impossible to “hack”. The key length is too big, and the total amount of possible keys is huge, so any kind of brute force will require too much time (or an unreally powerful computer). Trying to use the already compromised decryption keys is a way, but the efficiency of apps that offer such a function is pretty low.

Ransomware gets on your PC, not through magic. Cdtt ransomware uses dubious programs as the primary method of its distribution. “Free” versions of popular apps, cheat engines, Windows activators, and keygens are the most popular shells for all STOP/Djvu ransomware families, and the Cdtt virus is not an exclusion. Paying a small sum for a license is much easier than paying almost $1000 for the file decryption.

Encryption process

The Cdtt ransomware uses the Salsa20 encryption algorithm. That is not the strongest method, but it still provides an overwhelming amount of possible decryption keys. To brute force the 78-digit number of keys, you need 3.5 unvigintillion years (1*10^65), even if you use the most powerful regular PC. Quantum computers can show a bit better results, but it is still too slow to get your files back while you are alive.

The exact algorithm of encryption is next: malware scans each folder for the files it is able to encrypt. Then, when it finds the target, it makes a copy of your file, removes the original one, encrypts the copy and leaves it instead of the removed original. Such a procedure is done to prevent the situation when you have already opened the file, so ransomware is not able to read it because of the Windows restrictions. To each encrypted copy, the virus adds the specific extension - ".cdtt". Then, ransomware creates a _readme.txt file in the folder where the encrypted file is located, and goes to the next folder.

Such an encryption method can be exploited for file recovery. Since the original file is deleted, you may try to recover it using the file recovery tools. The less time is passed - the bigger the chance to get your files back, so hurry up!

Another specific moment that can help you to use the files even after the encryption is the fact that Cdtt ransomware encrypts only the first 150KB of each file. Hence, you can try to run a big file, such as video or music, without the encryption. Similar feature also works with other ransomware families - Dharma, Conti and Makop encrypt the same 150KB.

Ransom note: _readme.txt

Ransom note is the same for the whole ransomware family. In fact, it is one of the main signs of to which family the certain ransomware belongs. Here is the typical note for STOP/Djvu family:

External Links:

🔗 HowToFix.Guide: How To Decrypt .cdtt Files?

Indicators of Compromise(IOC)

File Name	MD5	File Size
📜 SAMPLE.EXE	32fbe6ae4b68107a8bd62276bcc06639	8108791
📜 SAMPLE.EXE	8b9ba9bf833fa984619178929803443d	1273856
📜 SAMPLE.EXE	e6f92be7f819410f58178b2a32c02ece	803328
📜 SAMPLE.EXE	e1e25cf99caaca5be73b35414a4a9a2b	946816
📜 SAMPLE.EXE	9934846e208068c2a5371068e92ee1f4	7960974
📜 SAMPLE.EXE	d93e1466e510a116d3613caac34c8845	688688
📜 SAMPLE.EXE	88c925303429aeb9bcec2e060fbf3d89	11439438
📜 SAMPLE.EXE	be1a93194fd9c33df52a6f2fea735e36	811597824
📜 SAMPLE.EXE	a9db8ab310c59a03c4a3fefcce691eae	1273856
📜 SAMPLE.EXE	cc134b8ddfe0681646ed11c0e3041876	756736