What is CVE-2026-56191?

CVE-2026-56191 is a security advisory published by Microsoft Security Response Center (MSRC) with Critical severity. Microsoft Exchange Online Tampering Vulnerability

Which CVE IDs does CVE-2026-56191 cover?

CVE-2026-56191 covers the following CVE IDs: CVE-2026-56191. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of CVE-2026-56191?

CVE-2026-56191 has a CVSS v3 base score of 10.0, published by Microsoft Security Response Center (MSRC).

CVE-2026-56191CriticalCVSS 10.0

Microsoft Exchange Online Tampering Vulnerability

Vendor

Microsoft Security Response Center (MSRC)

Published

July 23, 2026

Last Modified

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🔗 CVE IDs covered (1)

CVE-2026-56191 →

🔗 CVE IDs covered (1)

📋 Description