CVE-2021-43240
NTFS Set Short Name Elevation of Privilege Vulnerability
HIGH
7.8
CVSS Score
Published: December 15, 2021 at 02:15 PM UTC
Updated: June 17, 2026 at 04:10 AM UTC
14 products affected across 1 vendorWindows Server 2016Windows 10 1809Windows Server 2022
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Severity
HIGH7.8
Exploit prediction
EPSS 0.6%
SSVC
PoC
Description
NTFS Set Short Name Elevation of Privilege Vulnerability
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Affected range stops below 10.0.18363.1977, so it looks safe — our inference, not a vendor statement
All versions
Affected range stops below 10.0.19041.1415, so it looks safe — our inference, not a vendor statement
Affected range stops below 10.0.20348.405, so it looks safe — our inference, not a vendor statement
10.0.0 ≤ v < 10.0.19041.141510.0.0
Affected range stops below 10.0.19041.1415, so it looks safe — our inference, not a vendor statement
10.0.0 ≤ v < 10.0.19042.141510.0.0
Affected range stops below 10.0.19042.1415, 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:
Patch and advisory references
References (1)
x_refsource_MISCPatchVendor Advisory
Source: [email protected]
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43240SSVC — Action Prioritization
SSVCPoCNot automatableTotal impact
SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.
CVSS
7.8HIGHmicrosoft
Vector?
Quick Info
StatusMODIFIED
CWE
NVD-CWE-noinfo
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