Aesir ransomware virus: what it is and how to remove it

From our report of Nov 2016 · not reviewed since

Aesir virus is another version of infamous Locky ransomware

Aesir ransomware is the proof that the developers of the Locky virus are motivated and not willing to stop updating their hazardous malware.

Since its appearance at the beginning of 2016, malware has been updated several times. It took a little bit more than one month since Thor ransomware has hit the spotlight, and now Aesir virus started spreading and damaging personal files.

The recent version of the malware has lots of similarities with Thor; however, the main difference is new file extension appended during data encryption: instead of .thor extension, it puts .aesir extension. For this reason, malware is also known as .aesir file extension virus.

Similarly to Odin, Heimdall, Zepto and other Locky versions, this one also encrypts data using the same sophisticated set of RSA-2048 and AES-128 ciphers. During the encryption, malware distorts file names and renames them with random character strings, and appends new file extension. So, after encryption, example.jpg may look like D2DJY3Y6-6L54-DD34-6H76-5B154054HQ32.aesir. After file encryption, Aesir file virus drops two files "( )-INSTRUCTION.html" and "( )-INSTRUCTION.bmp".

BMP file becomes a new affected computer's background picture and gives guidelines where victim can find the ransom note in HTML format. The latter document includes all necessary information about data encryption. Moreover, victims learn that it is impossible to restore corrupted files unless they pay the ransom of 0.5 Bitcoins (about 360 USD).

In order to pay the ransom users have to install Tor browser and access Locky Decryptor website. They have to transfer money to the unique Bitcoin wallet, and as soon as the payment is made, they should be able to use a file decryption tool.

Unfortunately, computer users still do not backups their files regularly, so ransomware attacks seem horrible because they lose all the personal records. For this reason, paying the ransom may look like the only option. However, we want to discourage you from transferring Bitcoins to cyber criminals.

Their provided decryption tool may not work correctly or with decrypted files you may install other malware. Keep in mind that crooks may arrange another attack, because you paid necessary amount of money, hopefully, you will do it twice. At the end of the article, we provided instructions on how to remove Aesir automatically using or other professional malware removal tool.

Aesir ransomware virus has another unique feature. The virus doesn't need to contact its Command and Control servers to receive data encryption keys. This version of the malware uses C2 server, and the main concern is that antivirus programs cannot identify this ransomware activity. Indeed, the newest version of Locky became more dangerous, powerful and harder to avoid.

From our report of Nov 2016 · not reviewed since

How can I get infected with this ransomware?

The developers of the Aesir file virus use few distribution techniques; however, the most popular one stays malicious email attachments.

Cyber criminals spread infected file in JS, VBS, and ZIP formats. They launched different campaigns that trick users into opening fake invoices, statements, failed delivery status notifications and other "important" documents. Criminals may send an email informing about dispatched Amazon order or other message related to online shopping.

One of the recently discovered malware distribution campaigns pretends to be victims Internet service provider (ISP). The email claims that from the victim's computer has been sent spam and users are asked to have a look at attached logs. Fake logs are included in .zip file called _ .zip. However, this archive includes malware executable file.

However, just recently the developers of the Locky managed to get through Facebook's security and started spreading Aesir malware in this social network. The virus is distributed via malicious SVG file.

If victims click on this fake picture, he or she is redirected to the website which looks identical to YouTube. Here they are asked to install a particular plugin, and if they agree to do it, they install Nemucod – a Trojan responsible for installing and executing Aesir virus.

From our report of Nov 2016 · not reviewed since

Is it possible to remove Aesir ransomware and decrypt files?

Aesir virus belongs to the group of the most dangerous ransomware virus; however, its elimination is possible.

Do not think about removing the virus manually, because it's a complicated computer infection that may hide its malicious components under safe looking names, and you can accidentally delete important system files. Initiate Aesir removal with the help of professional antivirus or antimalware programs.

Before installing one of these tools, have a look at the instructions presented below. This version of the malware may prevent you from installing, updating or accessing security tools. In this case, you have to reboot the computer to the Safe Mode with Networking and follow the instructions.

Keep in mind that malware removal tools can only remove Aesir file virus; they cannot restore or decrypt corrupted files. Unfortunately, malware developers haven't managed to create a free decryption tool yet. Meanwhile, you can restore your files using data backups. If you do not have them, try additional data recovery methods presented below.

This professional tool has been created for locating and restoring missing or accidentally deleted files. However, it can be helpful in recovering at least some of the files encrypted by Aesir ransomware virus.