CRITICAL 9.0 Microsoft PoC

CVE-2021-34523

Microsoft Exchange Server Elevation of Privilege Vulnerability

Microsoft Security Update 2021-Jul: Microsoft Exchange Server Elevation of Privilege Vulnerability

Affected Products

References

Published: 2021-07-13 · Source: Microsoft · Feed updated: 2026-08-10
This critical severity vulnerability with a CVSS score of 9.0 was published on 2021-07-13 via Microsoft. 🚨 A public proof-of-concept exploit is available on GitHub. EPSS score: 100.0% (top 0% of all CVEs by exploitation probability). Affected: Microsoft Exchange Server 2013 Cumulative Update 23, Microsoft Exchange Server 2019 Cumulative Update 9, Microsoft Exchange Server 2016 Cumulative Update 20 and 2 more.

Risk Timeline

CVE Disclosed2021-07-13 · 1853 days ago
Public PoC Exploit AvailableWeaponised proof-of-concept code is publicly accessible

Remediation Resources

Official Advisory
msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34523
NVD / MITRE
nvd.nist.gov/vuln/detail/CVE-2021-34523

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