612
However , Microsoft did not highlight the SMB flaw until April 14 , when a hacker group known as the Shadow Brokers released a set of exploits , allegedly stolen from the U.S.National Security Agency .
 ( discover vulnerability: did not highlight,  Microsoft: vulnerable system owner, the SMB flaw: vulnerability, until April 14: 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:
 ( discover vulnerability: did not highlight,  Microsoft: vulnerable system owner, the SMB flaw: vulnerability, until April 14: time) 