CVE-2021-40469 — Windows DNS Server Remote Code Execution Vulnerability

Executive Summary

None

Overview

7.2

CVSS HIGH

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Remote Code Execution

Released Oct 12 2021

Last Updated Oct 12 2021

Publicly Disclosed Yes

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.06898 — 0.93249 percentile

NVD CVSS 7.2 HIGH — matches MSRC

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C

ATTACK VECTOR

Network

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

High

USER INTERACTION

None

SCOPE

Unchanged

CONFIDENTIALITY

High

INTEGRITY

High

AVAILABILITY

High

EXPLOIT CODE MATURITY

Proof-of-Concept

REMEDIATION LEVEL

Official Fix

REPORT CONFIDENCE

Confirmed

Temporal Score: 6.5

EPSS Score

0.06898

probability of exploitation in the next 30 days

0.93249 percentile - updated 2026-06-21

View on FIRST.org

Affected Products

8 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows Server 2008 for 32-bit Systems Service Pack 2 5006736 (Monthly Rollup) 5006715 (Security Only) Important Remote Code Execution 5005606 Base: 7.2 Temporal: 6.5 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C 6.0.6003.21251 Yes 5006736 5006715 Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation) 5006736 (Monthly Rollup) 5006715 (Security Only) Important Remote Code Execution 5005606 Base: 7.2 Temporal: 6.5 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C 6.0.6003.21251 Yes 5006736 5006715 Windows Server 2008 for x64-based Systems Service Pack 2 5006736 (Monthly Rollup) 5006715 (Security Only) Important Remote Code Execution 5005606 Base: 7.2 Temporal: 6.5 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C 6.0.6003.21251 Yes 5006736 5006715 Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation) 5006736 (Monthly Rollup) 5006715 (Security Only) Important Remote Code Execution 5005606 Base: 7.2 Temporal: 6.5 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C 6.0.6003.21251 Yes 5006736 5006715 Windows Server 2008 R2 for x64-based Systems Service Pack 1 5006743 (Monthly Rollup) 5006728 (Security Only) Important Remote Code Execution 5005633 Base: 7.2 Temporal: 6.5 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C 6.1.7601.25740 Yes 5006743 5006728 Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) 5006743 (Monthly Rollup) 5006728 (Security Only) Important Remote Code Execution 5005633 Base: 7.2 Temporal: 6.5 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C 6.1.7601.25740 Yes 5006743 5006728 Windows Server 2012 5006739 (Monthly Rollup) 5006732 (Security Only) Important Remote Code Execution 5005623 Base: 7.2 Temporal: 6.5 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C 6.2.9200.23490 Yes 5006739 5006732 Windows Server 2012 (Server Core installation) 5006739 (Monthly Rollup) 5006732 (Security Only) Important Remote Code Execution 5005623 Base: 7.2 Temporal: 6.5 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C 6.2.9200.23490 Yes 5006739 5006732 Windows Server 2012 R2 5006714 (Monthly Rollup) 5006729 (Security Only) Important Remote Code Execution 5005613 Base: 7.2 Temporal: 6.5 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C 6.3.9600.20144 Yes 5006714 5006729 Windows Server 2012 R2 (Server Core installation) 5006714 (Monthly Rollup) 5006729 (Security Only) Important Remote Code Execution 5005613 Base: 7.2 Temporal: 6.5 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C 6.3.9600.20144 Yes 5006714 5006729 Windows Server 2016	`5006669 (Security Update)`	Important	Remote Code Execution	Yes
Windows Server 2016 (Server Core installation)	`5006669 (Security Update)`	Important	Remote Code Execution	Yes
Windows Server 2019	`5006672 (Security Update)`	Important	Remote Code Execution	Yes
Windows Server 2019 (Server Core installation)	`5006672 (Security Update)`	Important	Remote Code Execution	Yes
Windows Server 2022	`5006699 (Security Update)`	Important	Remote Code Execution	Yes
Windows Server 2022 (Server Core installation)	`5006699 (Security Update)`	Important	Remote Code Execution	Yes
Windows Server, version 2004 (Server Core installation)	`5006670 (Security Update)`	Important	Remote Code Execution	Yes
Windows Server, version 20H2 (Server Core Installation)	`5006670 (Security Update)`	Important	Remote Code Execution	Yes

Patches

4 patches

Article	Type	Restart
`5006669`	Security Update	Yes
`5006672`	Security Update	Yes
`5006699`	Security Update	Yes
`5006670`	Security Update	Yes

Known Exploits

No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.

Acknowledgments

Shay Ber, Yuki Chen

References

MSRC Advisory MITRE NVD