CVE-2023-32020Network attack vector

Unauthenticated DNS spoofing via trusted reverse lookup

Published Jun 13, 2023 · Updated Jan 1, 2025

Spoofing in Microsoft Windows DNS Server allows remote attackers to corrupt DNS resolution via crafted network traffic. The public record maps the flaw to reliance on reverse DNS for a security-critical action, but Microsoft has not disclosed the affected code path or incorrect trust decision. The attack is network-reachable without authentication or user action, although successful spoofing depends on conditions Microsoft has not publicly described.

CVSS severity5.6
Medium
EPSS probability0.66%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Spoofing in Microsoft Windows DNS Server allows remote attackers to corrupt DNS resolution via crafted network traffic. The public record maps the flaw to reliance on reverse DNS for a security-critical action, but Microsoft has not disclosed the affected code path or incorrect trust decision. The attack is network-reachable without authentication or user action, although successful spoofing depends on conditions Microsoft has not publicly described.

The record

CVE
CVE-2023-32020
Published
Jun 13, 2023
Updated
Jan 1, 2025
Vendor
Microsoft
Product
Windows Server 2019
Classifications
CWE-350
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 13, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 1, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=10.0.17763.0 <10.0.17763.4499

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Microsoft · Windows Server 2019version=10.0.17763.0 <10.0.17763.4499
Microsoft · Windows Server 2016 (Server Core installation)version=10.0.14393.0 <10.0.14393.5989
Microsoft · Windows Server 2012 (Server Core installation)version=6.2.9200.0 <6.2.9200.24314
Microsoft · Windows Server 2012version=6.2.9200.0 <6.2.9200.24314
Microsoft · Windows Server 2016version=10.0.14393.0 <10.0.14393.5989
Microsoft · Windows Server 2008 R2 Service Pack 1version=6.1.7601.0 <6.1.7601.26564
Microsoft · Windows Server 2008 R2 Service Pack 1 (Server Core installation)version=6.1.7601.0 <6.1.7601.26564
Microsoft · Windows Server 2012 R2 (Server Core installation)version=6.3.9600.0 <6.3.9600.21013
Microsoft · Windows Server 2019 (Server Core installation)version=10.0.17763.0 <10.0.17763.4499
Microsoft · Windows Server 2008 Service Pack 2version=6.0.6003.0 <6.0.6003.22113
Microsoft · Windows Server 2022version=10.0.20348.0 <10.0.20348.1787
Microsoft · Windows Server 2012 R2version=6.3.9600.0 <6.3.9600.21013
Microsoft · Windows Server 2008 Service Pack 2 (Server Core installation)version=6.0.6003.0 <6.0.6003.22113

Published CVSS scores

5.6Microsoft CorporationCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-350Reliance on Reverse DNS Resolution for a Security-Critical Action

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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