This is a follow-up from our previous diary about todays ransomware attacks using the new Petya variant. So far, weve noted:
Samples of the new Petya variant are DLL files. So far, weve confirmed the following two SHA256 file hashes are the new variant:
Examining the new Petya variant
Petya is a ransomware family that works by modifying the infected Windows systems Master Boot Record (MBR). Using rundll32.exe with #1 as the DLL entry point, I was able to infect hosts in my lab with the above two DLL samples. The reboot didnt occur right away. However, when it did, my infected host did a CHKDSK after rebooting. border-width:2px” />
Shown above: An infected host immediately after rebooting.
After CHKDSK finished, the infected Windows hosts modified MBR prevented Windows from loading. border-width:2px” />
Shown above: The ransom note from a compromised system.
Samples of the new Petya variant appear to have WMI command-line (WMIC) functionality. Others have confirmed this variant spreads over Windows SMB and is reportedly using the EternalBlue exploit tool, which exploits CVE-2017-0144 and was originally released by the Shadow Brokers group in April 2017. border-width:2px” />
Shown above: Some of the traffic noted in my lab environment.
Keep in mind this is a new variant of Petya ransomware. Im still seeing samples of the regular Petya ransomware submitted to places like VirusTotal and other locations. From what we can tell, those previous versions of Petya are not related to today border-width:2px” />
Shown above: Difference in ransomware notes between the old and new Petya variants.
New Petya variant ransom message
Ooops, your important files are encrypted.
If you see this text, then your files are no longer accessible, because they have been encrypted. Perhaps you are busy looking for a way to recover your files, but dont waste your time. Nobody can recover your files without our decryption service.
We guarantee that you can recover all your files safely and easily. All you need to do is submit the payment and purchase the decryption key.
Please follow the instructions:
1. Send $300 worth of Bitcoin to the following address:
2. Send your Bitcoin walled ID and personal installation key to e-mail firstname.lastname@example.org. Your personal installation key:
If you already purchased your key, please enter it below.
More reports about the new Petya variant
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