161
Cyber researchers have tied the vulnerability exploited by Petya to the one used by WannaCry — a weakness discovered by the NSA years ago that the agency turned into a hacking tool dubbed EternalBlue .
 ( discover vulnerability: discovered,  a weakness: vulnerability, the NSA: discoverer, years ago: time, the vulnerability: vulnerability, exploited by Petya: capabilities, turned into a hacking tool: capabilities) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: phishing, data breach, ransom, discover vulnerability, patch vulnerability, Arguments type: vulnerable system, capabilities, vulnerability, number of victim, issues addressed, compromised data, damage amount, common vulnerabilities and exposures, victim, patch number, number of data, tool, discoverer, time, purpose, place, payment method, releaser, vulnerable system version, attacker, supported platform, patch, price, vulnerable system owner, trusted entity, attack pattern. 
Text: {0} 
Answer:
 ( discover vulnerability: discovered,  a weakness: vulnerability, the NSA: discoverer, years ago: time, the vulnerability: vulnerability, exploited by Petya: capabilities, turned into a hacking tool: capabilities) 