CVE-2021-26412
Microsoft Exchange Server Remote Code Execution Vulnerability
CRITICAL
9.1
CVSS Score
Published: March 2, 2021 at 11:55 PM UTC
Updated: August 19, 2026 at 05:17 PM UTC
1 product affected across 1 vendorExchange Server
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Severity
CRITICAL9.1
Exploit prediction
EPSS 34%
SSVC
PoC
Description
Microsoft Exchange Server Remote Code Execution Vulnerability
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
15.00.0 ≤ v < 15.00.1497.01215.01.0 ≤ v < 15.01.2106.01315.01.0 ≤ v < 15.01.2176.00915.02.0 ≤ v < 15.02.0721.01315.02.0 ≤ v < 15.02.0792.01015.00.015.01.015.02.02013 cumulative_update_232016 cumulative_update_182016 cumulative_update_192019 cumulative_update_72019 cumulative_update_8
Affected range stops below 15.00.1497.012, so it looks safe — our inference, not a vendor statement
Affected range stops below 15.01.2106.013, so it looks safe — our inference, not a vendor statement
Affected range stops below 15.01.2176.009, so it looks safe — our inference, not a vendor statement
Affected range stops below 15.02.0721.013, so it looks safe — our inference, not a vendor statement
Affected range stops below 15.02.0792.010, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
References (2)
PatchVendor Advisory
Source: [email protected]
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26412Vendor AdvisoryPatch
Source: cverecord
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26412SSVC — Action Prioritization
SSVCPoCAutomatablePartial impact
SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.
CVSS
9.1CRITICALmicrosoft
Vector?
Quick Info
StatusMODIFIED
CWE
NVD-CWE-noinfo
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