Dropbox employee whose password was exploited in the breach originally had his password exposed in the famous LinkedIn breach. This illustrates an interesting chaining or domino effect that data breaches can have across multiple organisations. Identity has become the new attack vector and hackers are all over that fact finding those orphaned accounts to grab and log-in to behind the scenes without an IT admin even knowing about it. The Dropbox incident could have been far worse had the impacted passwords not been encrypted.”]
Source: https://informationsecuritybuzz.com/articles/dropping-like-dominos/