An engineer received an alert of a zero-day vulnerability affecting desktop phones through which an...

 Upon receiving an alert of a zero-day vulnerability, the first step an engineer should take is to initiate a triage meeting to acknowledge the vulnerability and assess its potential impact2. This step is crucial for understanding the severity of the vulnerability, determining the scope of affected systems, and deciding on the subsequent actions to mitigate the risk. It involves gathering the relevant stakeholders and security experts to evaluate the threat and develop a response plan2.