What is WannaCrypt ransomware and how to stay safe

WannaCrypt Ransomware, also known by the names WannaCry, WanaCrypt0r or Wcrypt is a ransomware which targets Windows operating systems. Discovered on 12th May 2017, WannaCrypt was used in a large Cyber-attack and has since infected more than 230,000 Windows PCs in 190 countries now.


WannaCrypt initial hits include UK’s National Health Service, the Spanish telecommunications firm Telefónica, and the logistics firm FedEx. Such was the scale of the ransomware campaign that it caused chaos across hospitals in the United Kingdom. Many of them had to be shut down triggering operations closure on short notice, while the staff were forced to use pen and paper for their work with systems being locked by Ransomware.

How does WannaCrypt ransomware get into your computer

As evident from its worldwide attacks, WannaCrypt first gains access to the computer system via an email attachment and thereafter can spread rapidly through LAN. The ransomware can encrypt your systems hard disk and attempts to exploit the SMB vulnerability to spread to random computers on the Internet via TCP port and between computers on the same network.

Who created WannaCrypt

There are no confirmed reports on who has created WannaCrypt although WanaCrypt0r 2.0 looks to be the 2nd attempt made by its authors. Its predecessor, Ransomware WeCry, was discovered back in February this year and demanded 0.1 Bitcoin for unlocking.

Currently, the attackers are reportedly using Microsoft Windows exploit Eternal Blue which was allegedly created by the NSA. These tools have been reportedly stolen and leaked by a group called Shadow Brokers.

How does WannaCrypt spread

This Ransomware spreads by using a vulnerability in implementations of Server Message Block (SMB) in Windows systems. This exploit is named as EternalBlue which was reportedly stolen and misused by a group called Shadow Brokers.

Interestingly, EternalBlue is a hacking weapon developed by NSA to gain access and command the computers running Microsoft Windows. It was specifically designed for the America’s military intelligence unit to get an access to the computers used by the terrorists.

WannaCrypt creates an entry vector in machines still unpatched even after the fix had become available. WannaCrypt targets all Windows versions that were not patched for MS-17-010, which Microsoft released in March 2017 for Windows Vista, Windows Server 2008, Windows 7, Windows Server 2008 R2, Windows 8.1, Windows RT 8.1, Windows Server 2012, Windows Server 2012 R2, Windows 10 and Windows Server 2016.

The common infection pattern includes:

  • Arrival through social engineering emails designed to trick users to run the malware and activate the worm-spreading functionality with the SMB exploit. Reports say that the malware is being delivered in an infected Microsoft Word file that is sent in an email, disguised as a job offer, an invoice, or another relevant document.
  • Infection through SMB exploit when an unpatched computer can be addressed in other infected machinesThe worm functionality in WannaCrypt allows it to infect unpatched Windows machines in the local network. At the same time, it also executes massive scanning on Internet IP addresses to find and infect other vulnerable PCs. This activity results in large SMB traffic data coming from the infected host, and can be easily tracked by SecOps personnel.How to protect against Wannacrypt
  • Once WannaCrypt successfully infects a vulnerable machine, it uses it to hop to infect other PCs. The cycle further continues, as the scanning routing discovers unpatched computers.
  • WannaCrypt has rapid spreading capability
  1. Microsoft recommends upgrading to Windows 10 as it equipped with latest features and proactive mitigations.
  2. Install the security update MS17-010 released by Microsoft. The company has also released security patches for unsupported Windows versions like Windows XP, Windows Server 2003, etc.
  3. Windows users are advised to be extremely wary of Phishing email and be very careful while opening the email attachments or clicking on web-links.
  4. Make backups and  keep them securely
  5. Windows Defender Antivirus detects this threat as Ransom:Win32/WannaCrypt so enable and update and run Windows Defender Antivirus to detect this ransomware.
  6. Disable SMBv1 with the steps documented at KB2696547.
  7. Consider adding a rule on your router or firewall to block incoming SMB traffic on port 445
  8. Enterprise users may use Device Guard to lock down devices and provide kernel-level virtualization-based security, allowing only trusted applications to run.

To know more on this topic read the Technet blog.

The initial WannaCrypt attack may have been stopped, but we should expect a newer variant to strike more furiously moving forward, so stay safe and secure.

Our Immediate Recommendations are to AVOID clicking on any attachments sent to you via Email. EVEN IF THEY APPEAR TO BE LEGITIMATE!

Although the first wave of this Ransomware was stopped we are already seeing new variations if it hitting computers around the world. Finally – If you see the message as shown in this email blast, it’s already too late for you – IMMEDIATEL SHUT DOWN YOUR COMPUTER and call support.

Additional Information United States Computer Emergency Readiness (US – Cert Alert (TA17-132A)

Special thanks to The Windows Club for this information: http://www.thewindowsclub.com/what-is-wannacrypt-ransomware

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