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Researcher Artem Moskowsky told The Register earlier this week that he stumbled across the vulnerability – which earned him a $ 20,000 bug bounty for reporting it – by accident while looking over the Steam partner portal .
 discover vulnerability: stumbled
Please tell me event type and its trigger word from given type options. Output format is "type: trigger".  Option: phishing, data breach, ransom, discover vulnerability, patch vulnerability 
Text: {0} 
Answer:
 discover vulnerability: stumbled