CVE-2025-20077

Denial of service via unreleased firmware memory

Published Aug 12, 2025 · Updated Aug 12, 2025

Missing memory release in Intel UEFI OobRasMmbiHandlerDriver on Xeon 6 servers allows local users with high privileges to cause denial of service. The module retains memory after its effective lifetime instead of releasing it; Intel has not disclosed the triggering operation or precise failure mode. High privileges and local access are required, and the reported consequence is limited to service interruption.

CVSS severity5.3
Medium
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing memory release in Intel UEFI OobRasMmbiHandlerDriver on Xeon 6 servers allows local users with high privileges to cause denial of service. The module retains memory after its effective lifetime instead of releasing it; Intel has not disclosed the triggering operation or precise failure mode. High privileges and local access are required, and the reported consequence is limited to service interruption.

The record

CVE
CVE-2025-20077
Published
Aug 12, 2025
Updated
Aug 12, 2025
Vendor
Topcon Positioning Systems, Inc.
Product
Intel UEFI Reference Firmware
Classifications
CWE-401, T1499.004
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Aug 12, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 12, 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?

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  1. Affected versionversion=See references

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Topcon Positioning Systems, Inc. · Intel UEFI Reference Firmwareversion=See references

Published CVSS scores

5.3Intel CorporationCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:N/I:N/A:H
5.6Intel CorporationCVSS:4.0/AV:L/AC:H/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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

CWE-401Missing Release of Memory after Effective Lifetime
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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