CVE-2023-38163

Security feature bypass

Published Sep 12, 2023 · Updated Oct 30, 2025

Security feature bypass in Microsoft Defender Security Intelligence Updates before 1.391.1332.0 allows local users to bypass Attack Surface Reduction controls. Microsoft does not publicly disclose the component or operation that permits the bypass, so the precise mechanism remains undocumented. Exploitation requires local execution on a Windows device using affected Defender intelligence content; the documented impact is circumvention of the intended security control rather than a separately demonstrated confidentiality, integrity, or availability compromise.

CVSS severity7.8
High
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

Security feature bypass in Microsoft Defender Security Intelligence Updates before 1.391.1332.0 allows local users to bypass Attack Surface Reduction controls. Microsoft does not publicly disclose the component or operation that permits the bypass, so the precise mechanism remains undocumented. Exploitation requires local execution on a Windows device using affected Defender intelligence content; the documented impact is circumvention of the intended security control rather than a separately demonstrated confidentiality, integrity, or availability compromise.

The record

CVE
CVE-2023-38163
Published
Sep 12, 2023
Updated
Oct 30, 2025
Vendor
Microsoft
Product
Microsoft Defender Security Intelligence Updates
Classifications
T1562.001
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 12, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 30, 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=1.0.0 <1.391.1332.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Microsoft · Microsoft Defender Security Intelligence Updatesversion=1.0.0 <1.391.1332.0

Published CVSS scores

7.8Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1562.001Impair Defenses: Disable or Modify Tools

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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