Secrets logged at scale
A developer notices during debugging that the payment service has been writing the full request body — including raw card numbers and a third-party processor API key passed in a header — into structured application logs since a logging change deployed 8 days ago. Those logs ship to your centralized logging platform (retained 90 days, searchable by ~200 employees) and a copy goes to a third-party log-analytics vendor. You're the on-call engineer who's been escalated to. Triage and contain.
What a strong answer looks like
Stop the bleeding first (mitigate), then form hypotheses from real signals. Separate root cause from symptom, communicate status as you go, and close with what prevents a repeat.
0:00 of about 30 min
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.
Run or narrate your approach, then ask the coach.