CVE-2023-32021Network attack vector

Authenticated SMB Witness service disruption

Published Jun 13, 2023 · Updated Jan 1, 2025

Security feature bypass in Microsoft Windows Server 2012 R2 through 2022 allows remote authenticated users to disrupt the SMB Witness service. Microsoft has not published the flawed function, request field, or incorrect operation within the SMB Witness implementation. Network access with low privileges is required; exploitation interrupts service availability and permits limited modification without data disclosure.

CVSS severity7.1
High
EPSS probability1.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Security feature bypass in Microsoft Windows Server 2012 R2 through 2022 allows remote authenticated users to disrupt the SMB Witness service. Microsoft has not published the flawed function, request field, or incorrect operation within the SMB Witness implementation. Network access with low privileges is required; exploitation interrupts service availability and permits limited modification without data disclosure.

The record

CVE
CVE-2023-32021
Published
Jun 13, 2023
Updated
Jan 1, 2025
Vendor
Microsoft
Product
Windows Server 2019
Classifications
T1499.004
Attack vector
network
Privileges
authenticated

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

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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=10.0.17763.0 <10.0.17763.4499

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

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 2016version=10.0.14393.0 <10.0.14393.5989
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 2022version=10.0.20348.0 <10.0.20348.1787
Microsoft · Windows Server 2012 R2version=6.3.9600.0 <6.3.9600.21013

Published CVSS scores

7.1Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

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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