Everything you need to know about the Petya, er, NotPetya nasty trashing PCs worldwide

http://www.theregister.co.uk/2017/06/28/petya_notpetya_ransomware/

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Here's a summary of the NotPetya outbreak:

The malware uses a bunch of tools to move through a network, infecting machines as it goes. It uses a tweaked build of open-source Minikatz to extract network administrator credentials out of the machine's running memory. It uses these details to connect to and execute commands on other machines using PsExec and WMIC to infect them.

It also uses a modified version of the NSA's stolen and leaked EternalBlue SMB exploit, previously used by WannaCry, plus the agency's stolen and leaked EternalRomance SMB exploit, to infect other systems by injecting malicious code into them. These cyber-weapons attack vulnerabilities patched by Microsoft earlier this year, so the credential theft is usually more successful, at least at places that are on top of their Windows updates.

Crucially, NotPetya seeks to gain administrator access on a machine and then leverages that power to commandeer other computers on the network: it takes advantage of the fact that far too many organizations employ flat networks in which an administrator on one endpoint can control other machines, or sniff domain admin credentials present in memory, until total control over the Windows network is achieved.

One way to gain admin access is to use the NSA exploits. Another way is to trick a user logged in as an admin or domain admin into running a booby-trapped email attachment that installs and runs the malware with high privileges. Another way is to feed a malicious software update to an application suite running as admin or domain admin, which starts running the malware on the corporate network again with high privileges. It is understood NotPetya got into corporate networks as an admin via a hijacked software update for a Ukrainian tax software tool, and via phishing emails.

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