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Cyber researchers say that the virus , which was linked to malware called Petrwrap or Petya , used an “ exploit ” developed by the National Security Agency that was later leaked onto the Internet by hackers .
 ( data breach: leaked,  an “ exploit ”: compromised data, the National Security Agency: victim, hackers: attacker) 
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:
 ( data breach: leaked,  an “ exploit ”: compromised data, the National Security Agency: victim, hackers: attacker) 