Ransomware Changes Extension

Thursday, September 29, 2016 @ 05:09 PM gHale

Locky added a new extension that appends to encrypted files and could add to victims’ confusion.

In early summer, researchers found Locky switched to the .zepto extension, which has been used in multiple campaigns since, said researchers at BleepingComputer.

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Now, Locky is appending the .ODIN extension to encrypted files, which is bound to create some confusion, as victims might believe they have been infected with a new ransomware variant.

However, BleepingComputer’s Lawrence Abrams said in a blog post this is not the Odin ransomware, but in fact Locky, which is using the .ODIN extension instead of .zepto.

Just as before, the new malware version is distributed via spam emails containing script files as attachments. As soon as the recipient opens the attachment, the malicious code in these script files downloads an encrypted DLL installer, after which it decrypts and executes to infect the system with Locky.

Once executed, the ransomware encrypts user’s files, renames them, and appends the .ODIN extension. Then, the malware drops ransom notes on the system to inform the user on the attack.

In this new variant, the names of the ransom notes have been changed to _HOWDO_text.html, _HOWDO_text.bmp, and _[2_digit_number]_HOWDO_text.html.