New Ransomware virus called Mamba also known as HDDCryptor has been discovered via a malicious files, named “141.exe” and “152.exe” that uses AES encryption to fully encrypt a hard drive and not let users to even boot Windows. This new tendency for ransomware viruses is continuing to grow and is not likely to fade away soon. Such encryption prevents the user from completely accessing the hard drive and hence the files in it. This way, it becomes significantly more complicated to try and decrypt your files or restore them using any data recovery software. It simply prevents any access to the hard drive, because it, itself is AES encrypted.
Threat Summary
| Name | Mamba |
| Type | Ransomware |
| Short Description | The malware encrypts the hard drive of the user with a custom password, denying all access to it. It asks for 1 BTC ransom payment to send a password for encryption. |
| Symptoms | On system boot displays the following ransom note – “You are Hacked ! H.D.D. Encrypted , Contact Us For Decryption Key ([email protected]) YOURID: {ID}” |
| Distribution Method | Via an Exploit kit, Dll file attack, malicious JavaScript or a drive-by download of the malware itself in an obfuscated manner. Malicious executables with numbers detected (for example 133.exe). |
| Detection Tool |
See If Your System Has Been Affected by Mamba
Download Malware Removal Tool |
| User Experience | Join our forum to Discuss Mamba Ransomware. |
| Data Recovery Tool | Windows Data Recovery by Stellar Phoenix Notice! This product scans your drive sectors to recover lost files and it may not recover 100% of the encrypted files, but only few of them, depending on the situation and whether or not you have reformatted your drive. |
Mamba Virus – How Does It Infect?
The ransomware is reported by the researcher who discovered it, Renato Marinho to infect users using a malicious executable that has a file name consisting of 3 numbers. The researcher searched a file, called 141.exe which was related to the malware and several detections rendered it as a Ransom_HDDCRYPTOR_A (TrendMicro). What is interesting is how the researchers came to see the ransomware – it attacked a whole company’s network of devices and had a user ID for the computer it encrypted. This is a strong indicator that the Mamba virus may be spread via other, compromised computers with other malware.
Mamba Ransomware – In-Depth Analysis
When further researched and tested on a computer running a Windows 8.1 virtual machine the virus activated and created a folder in C: drive with the following files:
- C:\DC22\dcapi.dll
- C:\DC22\dccon.exe
- C:\DC22\dcinst.exe
- C:\DC22\dcrypt.exe
- C:\DC22\dcrypt.sys
- C:\DC22\log_file.txt
- C:\DC22\Mount.exe
- C:\DC22\netpass.exe
- C:\DC22\netpass.txt
- C:\DC22\netuse.txt
When we checked the name dcrypt ourselves, we have established that it is a project that is completely open source and can be downloaded from Sourceforge. Another program which they may have used is reported by the researchers to be called DiskCryptor. It is essentially a tool that combines several algorithms, creating a password and making it difficult for hackers to access a drive. Well, the joke is on the victim because the hackers have learned to use this free tool to make Mamba ransomware.
After these files are created Windows automatically restarts and the virus obtains different information, like share drive data and other info. Mamba ransomware then installs additional malicious files and services that are running like ghosts on the victim PC. One of the services this virus also creates, was reported by the researchers to be called “DefragmentService”, being located in the following path:
In addition to this, the Mamba Ransomware creates a new user on the encrypted computer as well.
Renato Marinho and his team reported to try and run the dcrypt.exe and other executables, but they report several failed attempts until they finally saw the VM reboot after which the following ransom message was displayed:
The experienced researchers were also able to detect which process caused the encryption, a file named dccon.exe, located in the C:\DC22\ folder. The file executed the following parameters to encrypt the drive:
→ Device: \Device\HarddiskVolume1
SymLink: \\?\Volume{11788659-88c2-11e5-bf9c-806e6f6e6963}
Mount point: C:
Capacity: 39.9 GB
Status: mounted, boot, system
Cipher: AES
Encryption mode: XTS
Pkcs5.2 prf: HMAC-SHA-512
Encrypted portion: 100.000%
This information strongly suggests an AES-512 cipher with an encryption mode of XTS mode may have been used instead of the claimed 2048 by the cyber-criminals on the other side of the e-mail address in the note.
Mamba Ransomware – Conclusion and How to Fix It
Malware researchers are strongly convinced that there is one unified password for all of the encrypted drives, this virus may have encoded so far. Upon contacting the e-mail address they received the following reply:
In case you see the ransom message of this virus, we strongly suggest you NOT to pay any ransom money to cyber-criminals, because, just like Petya and Mischa ransomware variants encrypting hard drives, a solution may be discovered for this virus very soon. In the meantime, we advise you to unplug the hard drive from your computer using the following instructions:
They are created for another virus of the same type, for which there is a decryptor released. You can see step 1 to step 3 in the “Decryption Phase” of the instructions how to remove your hard drive. Then simply keep the hard drive intact and do not try to tamper with it. Instead, we advise you to purchase a new drive in the meantime and install an advanced anti-malware program that will ensure that you are protected in the future. Expect an update with an instructions URL on this article as soon as a free decryption solution is released.
See If Your System Has Been Affected by Mamba
It is highly recommended to run a scan before purchasing the full version of the software to make sure that the current version of the malware can be detected by SpyHunter.
- jbl
- Vencislav Krustev
- ofk
