CVE-2023-27471

Platform denial of service via MeSetup overwrite

Published Aug 18, 2023 · Updated Oct 7, 2024

Denial of service in Insyde InsydeH2O kernel 5.0 through 5.5 allows local users to interrupt the platform through a UEFI variable overwrite. The firmware fails to protect and validate the MeSetup UEFI variable, allowing operating system APIs to replace its contents on affected systems. Exploitation requires local administrative privileges and causes platform denial of service; the resulting failure mode is not publicly specified.

CVSS severity4.1
Medium
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Insyde InsydeH2O kernel 5.0 through 5.5 allows local users to interrupt the platform through a UEFI variable overwrite. The firmware fails to protect and validate the MeSetup UEFI variable, allowing operating system APIs to replace its contents on affected systems. Exploitation requires local administrative privileges and causes platform denial of service; the resulting failure mode is not publicly specified.

The record

CVE
CVE-2023-27471
Published
Aug 18, 2023
Updated
Oct 7, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1499
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Aug 18, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 7, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
4.1Insyde SoftwareCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

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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