2554
Half a million smart devices including webcams and baby monitors in the city are currently vulnerable to cyber attack .
 ( discover vulnerability: are currently vulnerable,  baby monitors: vulnerable system, webcams: vulnerable system, smart devices: vulnerable system) 
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: are currently vulnerable,  baby monitors: vulnerable system, webcams: vulnerable system, smart devices: vulnerable system) 