Outlook CVE-2026-21260
HIGHCVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Lifecycle Timeline
2DescriptionNVD
Exposure of sensitive information to an unauthorized actor in Microsoft Office Outlook allows an unauthorized attacker to perform spoofing over a network.
AnalysisAI
Information disclosure in Microsoft Outlook, SharePoint Server, Office, and 365 Apps enables remote attackers to conduct email spoofing attacks without authentication or user interaction. The vulnerability affects multiple Microsoft collaboration products and could allow threat actors to impersonate legitimate senders to compromise organizational security. …
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RemediationAI
Within 24 hours: Notify all users of the spoofing risk and establish guidelines for verifying sender authenticity through out-of-band communication; escalate to Microsoft for patch timeline. Within 7 days: Implement email gateway controls to detect and flag anomalous sender patterns; segment critical business processes to require secondary verification for sensitive transactions. …
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External POC / Exploit Code
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