561
But Gregory said it would be “ self - defeating ” for hackers not to release data upon receipt of a ransom , “ because that would immediately hit the media , and no one would pay ” .
 ( ransom: receipt of a ransom,  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:
 ( ransom: receipt of a ransom,  hackers: attacker) 