Attackers breach Microsoft 365 accounts across 79 organizations

The campaign reused stolen login tokens and produced at least 497 successful sign-ins between July 14 and September 22, 2026. Huntress, which monitored the activity during that period, said attackers used an adversary-in-the-middle relay to capture sign-in sessions before accessing email accounts, according to The Hacker News.

• The Hacker News reported 97 compromised accounts.
• More than 200,000 failed login attempts were recorded, according to Cyber Security News.

Covered by 2 publishers within 22 hours of the first report.

• The Hacker News: Microsoft 365 Token-Replay Attacks Compromise 97 Accounts at 79 Organizations

Reporting2

THN The Hacker News Microsoft 365 Token-Replay Attacks Compromise 97 Accounts at 79 Organizations · info@thehackernews.com (The Hacker News) 4:35 AM

CSN Cyber Security News Hackers Hijack Microsoft 365 Accounts at 79 Organizations Using Stolen Login Tokens · Tushar Subhra Dutta 2:57 AM

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Topics MicrosoftData breaches