CVE-2021-34523 — Microsoft Exchange Server Privilege Escalation Vulnerability

CVE-2021-34523

CRITICAL · CVSS 9 ⚠ KEV — EXPLOITED

EPSS exploitation probability: 100%

⚠ Listed in the CISA Known Exploited Vulnerabilities catalog — actively exploited.

Published 2021-11-03 · Last modified 2026-08-10T16:17:56.847

Summary

Microsoft Exchange Server Elevation of Privilege Vulnerability

Microsoft — Exchange Server

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