Description Summary
WannaCry ransomware is a cyber attack that spreads by exploiting vulnerabilities in the Windows operating system. At its peak in May 2017, WannaCry became a global threat. Cybercriminals used the ransomware to hold an organization's data hostage and extort money in the form of cryptocurrency. WannaCry spreads using EternalBlue, an exploit leaked from the National Security Agency (NSA). EternalBlue enables attackers to use a zero-day vulnerability to gain access to a system. It targets Windows computers that use a legacy version of the Server Message Block (SMB) protocol.
Threat Actor
Attributed by the U.S., U.K. and allied governments to the Lazarus Group (North Korea). Not a leak-site/extortion crew — WannaCry was a self-propagating worm, and its spread was halted when a researcher (Marcus Hutchins) registered its kill-switch domain.
Technical Indicators
.WNCRY (also .WCRY; temporary files use .wncryt)
AES-128 (CBC) for files + RSA-2048 (key wrapping)
@Please_Read_Me@.txt (plus the 'Wana Decrypt0r 2.0' GUI / @WanaDecryptor@.exe)
Cross-sector — notably Healthcare (UK NHS), Telecommunications, Manufacturing, Logistics
12 May 2017
May 2017 (outbreak halted by the kill-switch domain; unpatched variants persist)
Worldwide — ~230,000 systems across 150+ countries
MITRE ATT&CK Matrix
| Tactic | TTP | Technique Name |
|---|---|---|
| Lateral Movement x 3 | T1210 | Exploitation of Remote Services (EternalBlue / MS17-010) |
| T1021.002 | SMB/Windows Admin Shares | |
| T1570 | Lateral Tool Transfer (worm self-propagation) | |
| Impact x 3 | T1486 | Data Encrypted for Impact |
| T1490 | Inhibit System Recovery (deletes shadow copies) | |
| T1489 | Service Stop |