WannaCry

WannaCry

Screenshot of the ransom note left on an infected system
Date	12 May 2017 – 15 May 2017 (initial outbreak)
Location	Worldwide
Also known as	Transformations: Wanna → Wana Cryptor → Crypt0r Cryptor → Decryptor Cryptor → Crypt → Cry Addition of "2.0" Short names: Wanna → WN → W Cry → CRY
Type	Cyberattack
Theme	Ransomware encrypting files with $300 – $600 demand (via bitcoin)
Cause	WannaCry worm
Outcome	Over 200,000 victims and more than 300,000 computers infected

The WannaCry ransomware attack was a May 2017 worldwide cyberattack by the WannaCryransomware cryptoworm, which targeted computers running the Microsoft Windows operating system by encrypting data and demanding ransom payments in the Bitcoin .

The attack began on Friday, 12 May 2017, and within a day was reported to have infected more than 230,000 computers in over 150 countries. Parts of the United Kingdom's National Health Service (NHS) were infected, causing it to run some services on an emergency-only basis during the attack, Spain's Telefónica, FedEx and Deutsche Bahn were hit, along with many other countries and companies worldwide. Shortly after the attack began, Marcus Hutchins, a 22-year-old web security researcher from North Devon in England then known as MalwareTech discovered an effective kill switch by registering a domain name he found in the code of the ransomware. This greatly slowed the spread of the infection, effectively halting the initial outbreak on Monday, 15 May 2017, but new versions have since been detected that lack the kill switch. Researchers have also found ways to recover data from infected machines under some circumstances.

WannaCry propagates using EternalBlue, an exploit of Windows' Server Message Block (SMB) protocol. Much of the attention and comment around the event was occasioned by the fact that the U.S. National Security Agency (NSA) had already discovered the vulnerability, but used it to create an exploit for its own offensive work, rather than report it to Microsoft. Microsoft eventually discovered the vulnerability, and on Tuesday, March 14, 2017, they issued security bulletin MS17-010, which detailed the flaw and announced that patches had been released for all Windows versions that were currently supported at that time, these being Windows 7, Windows 8.1, Windows 10, Windows Server 2008, Windows Server 2012, and Windows Server 2016, in addition to Windows Vista (which had recently ended support). However, many Windows users had not installed the patches when, two months later on May 12, 2017, WannaCry used the EternalBlue vulnerability to spread itself. The next day, Microsoft released emergency security patches for Windows 7 and Windows 8.