CVE-2021-38626

Local elevation of privilege through undisclosed kernel flaw

Published Sep 15, 2021 · Updated Aug 10, 2026

Windows Kernel in Windows Server 2008 SP2 before 6.0.6003.21218 allows local users to elevate privileges through a crafted application. Microsoft has not published the vulnerable kernel locus or the incorrect operation it performs on attacker-controlled input. A low-privilege local account and execution on the target host are required; successful exploitation elevates that account on the affected host.

CVSS severity7.8
High
EPSS probability0.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Windows Kernel in Windows Server 2008 SP2 before 6.0.6003.21218 allows local users to elevate privileges through a crafted application. Microsoft has not published the vulnerable kernel locus or the incorrect operation it performs on attacker-controlled input. A low-privilege local account and execution on the target host are required; successful exploitation elevates that account on the affected host.

The record

CVE
CVE-2021-38626
Published
Sep 15, 2021
Updated
Aug 10, 2026
Vendor
Microsoft
Product
Windows Server 2008 Service Pack 2
Classifications
CWE-269, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=6.0.6003.0 <6.0.6003.21218

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Microsoft · Windows Server 2008 Service Pack 2version=6.0.6003.0 <6.0.6003.21218
Microsoft · Windows Server 2008 Service Pack 2 (Server Core installation)version=6.0.6003.0 <6.0.6003.21218

Published CVSS scores

7.8Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
4.6NIST National Vulnerability DatabaseAV:L/AC:L/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-269Improper Privilege Management
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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