Critical

Attackers Use Passkey Phishing to Hijack Microsoft Cloud Accounts and Exfiltrate Data

The Hacker News
Actively Exploited

Overview

Microsoft has reported two recent phishing campaigns where attackers exploited third-party email services to send out fraudulent messages. Between August 3 and 5, 2026, more than a million scam emails were dispatched, impersonating CEOs to deceive recipients. These campaigns utilized social engineering tactics focused on passkeys to gain unauthorized access to Microsoft cloud accounts, leading to potential data breaches. As a result, both individuals and organizations using Microsoft cloud services could be at risk of financial fraud and data exfiltration. This incident underscores the ongoing challenges in cybersecurity, particularly in safeguarding sensitive information against increasingly sophisticated phishing attempts.

Key Takeaways

  • Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
  • Affected Systems: Microsoft cloud accounts
  • Action Required: Users should implement multi-factor authentication, be cautious of unsolicited emails, and verify the sender's identity before clicking on links or providing sensitive information.
  • Timeline: Newly disclosed

Original Article Summary

Microsoft has disclosed details of two campaigns in which threat actors are abusing third-party email delivery infrastructure to blast financial fraud scam messages and using passkey-themed social engineering to breach cloud environments. The first campaign, per the tech giant, involved sending over a million scam emails between August 3 and 5, 2026, by masquerading as chief executive officers

Impact

Microsoft cloud accounts

Exploitation Status

This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.

Timeline

Newly disclosed

Remediation

Users should implement multi-factor authentication, be cautious of unsolicited emails, and verify the sender's identity before clicking on links or providing sensitive information.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to Phishing, Microsoft, Data Breach.

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