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A new variant of the WannaCry ransomware attack surfaced on Monday , according to cyber security firm Check Point Software , which it said it had stopped from damaging computers by activating a " kill switch " in the software .
 ( ransom: the WannaCry ransomware attack,  Monday: time) 
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: the WannaCry ransomware attack,  Monday: time) 