Looy Virus Ransomware (.looy File)

What is Looy ransomware?

It is hard to imagine something more dangerous than a ransomware attack. But, unfortunately, in the modern computer world, only ransomware creates so much fear around itself. Looy ransomware, however, cannot be as dangerous as some other examples of this malware type, but it still makes your files inaccessible and corrupts many functions on your PC.

The cipher Looy virus uses Salsa20 - not the strongest one, but you still have no chance to decrypt it. Specialized software can help you, but the stakes will still be low - there are too many possible keys, and too few of them are uncovered. Compromised keys are collected by cybersecurity experts and added to the decryption tools’ databases. Who knows, maybe one will fit you?

Another danger this virus carries hides in Windows configurations. Such a big security breach cannot leave without attention from the virus creators. Looy ransomware changes some arrangements, and voila - you cannot run the installation files of antivirus programs and cannot open the sites with virus removal information. It also sometimes blocks access to the servers of decryption tools, so the last ones can’t update their decryption keys databases. The sooner you will remove these changes - the fewer problems you will have in the future.

Ransomware distribution is committed in many ways. Since Looy ransomware is targeted primarily at individuals, its developers chose dubious sites&hacked software as a primary spreading way. Downloading the “free” 3DS Max or Windows activation tool may result in a ransomware attack. Isn’t it easier and cheaper to pay ~<$50 for a license than to pay $1000 for file recovery?

Encryption process

The Looy 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 - ".looy". 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 Looy 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 .looy Files?

Indicators of Compromise(IOC)

File Name	MD5	File Size
📜 SAMPLE.EXE	2dad0e56430b3af51313af22979a8376	1273856
📜 SAMPLE.EXE	fa0fdb300f7d2b2f4971908b19796c47	837632
📜 SAMPLE.EXE	63ad57b77c144c54c3963bd17b58effb	738816
📜 SAMPLE.EXE	51cdffb93a6be165bbf7657410530d0d	772608
📜 SAMPLE.EXE	e6508292f27399e540c7916734488cb1	787968
📜 SAMPLE.EXE	ea3bf14249d2bfe8a93603b597bd9b30	787968
📜 SAMPLE.EXE	1c8b13f43b2fdad14032b7f82441fb0a	755712
📜 SAMPLE.EXE	136439d2e29ce03a95b7cfc86838f27a	769536
📜 SAMPLE.EXE	ac082d5f48200f4358291a225ee23e5b	756224
📜 SAMPLE.EXE	a3a0ab5719e2efe51f2df19014fb758c	756224