CVE-2021-26332

State corruption or service interruption via MMIO-overlapping TMR

Published May 10, 2022 · Updated Sep 16, 2024

SEV-ES firmware validation failure in 3rd Gen AMD EPYC processors before MilanPI-SP3_1.0.0.4 allows local users to corrupt state or interrupt service. The firmware accepts a trusted memory region without rejecting an address range that overlaps memory-mapped I/O. A local low-privileged user can reach the flaw on an affected SEV-ES host; AMD reports integrity or availability loss but no confidentiality impact.

CVSS severity7.1
High
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

SEV-ES firmware validation failure in 3rd Gen AMD EPYC processors before MilanPI-SP3_1.0.0.4 allows local users to corrupt state or interrupt service. The firmware accepts a trusted memory region without rejecting an address range that overlaps memory-mapped I/O. A local low-privileged user can reach the flaw on an affected SEV-ES host; AMD reports integrity or availability loss but no confidentiality impact.

The record

CVE
CVE-2021-26332
Published
May 10, 2022
Updated
Sep 16, 2024
Vendor
Advanced Micro Devices, Inc.
Product
3rd Gen AMD EPYC Processors
Classifications
T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 10, 2022CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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?

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

  1. Affected versionversion=unspecified <MilanPI-SP3_1.0.0.4

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Advanced Micro Devices, Inc. · 3rd Gen AMD EPYC Processorsversion=unspecified <MilanPI-SP3_1.0.0.4

Published CVSS scores

6.6NIST NVDAV:L/AC:L/Au:N/C:N/I:C/A:C
7.1NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/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
Privilegesauthenticated
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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