Hackers Broke Into Microsoft 365 Through Forgotten Accounts Nobody Was Watching

Hackers have breached Microsoft 365 environments by targeting accounts that were still active but unmonitored. An old password and missing sign-in protections gave intruders a route into email, files, and cloud applications. The campaign focused heavily on organisations in Chile, including a large retailer and financial institutions. Rather than repeatedly guessing passwords for one person, the operator tested likely default passwords across many accounts, a technique seen in similar password spraying attacks, then used successful logins to explore cloud services. Proofpoint analysts identified the activity as UNK_CondorFiltration, a campaign abusing TeamFiltration, a testing framework…