CVE-2021-26387

Platform-integrity loss via protected DRAM mapping

Published Aug 13, 2024 · Updated Oct 30, 2024

Incorrect authorization in the ASP kernel in affected AMD processor families allows privileged attackers to compromise platform integrity. The kernel fails to prevent signed ASP firmware from mapping DRAM regions designated as protected. Exploitation requires AMD signing keys and access to the BIOS menu or UEFI shell; successful mapping can alter protected platform memory or interrupt operation.

CVSS severity3.9
Low
EPSS probability0.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect authorization in the ASP kernel in affected AMD processor families allows privileged attackers to compromise platform integrity. The kernel fails to prevent signed ASP firmware from mapping DRAM regions designated as protected. Exploitation requires AMD signing keys and access to the BIOS menu or UEFI shell; successful mapping can alter protected platform memory or interrupt operation.

The record

CVE
CVE-2021-26387
Published
Aug 13, 2024
Updated
Oct 30, 2024
Vendor
Advanced Micro Devices, Inc.
Product
AMD Ryzen™ 7000 Series Desktop Processors
Classifications
CWE-863, T1542.001
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Aug 13, 2024CVE publishedPublication date reported by the CVE source.
  2. Oct 30, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Advanced Micro Devices, Inc. · AMD Ryzen™ 7000 Series Desktop ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ Embedded V1000 Series ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ 3000 Series Processors with Radeon™ GraphicsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen Threadripper PRO 5000WX ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Athlon™ 3000 Series Desktop Processors with Radeon™ GraphicsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ Embedded R2000 Series ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD EPYC Embedded 7003 Series Processorsversion=various
Advanced Micro Devices, Inc. · AMD EPYC Embedded 7002 Series Processorsversion=various
Advanced Micro Devices, Inc. · AMD EPYC Embedded 9003 Series Processorsversion=various
Advanced Micro Devices, Inc. · AMD Athlon™ 3000 Series Mobile Processors with Radeon™ GraphicsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ Threadripper™ PRO 3000WX Series ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ Embedded V3000 Series ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ Threadripper™ 3000 Series ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen Embedded V2000 Series ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD EPYC Embedded 3000 Series Processorsversion=various
Advanced Micro Devices, Inc. · AMD Ryzen™ Embedded 5000 Series ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ 5000 Series Mobile Processors with Radeon™ GraphicsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ 6000 Series Processors with Radeon™ GraphicsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ 4000 Series Desktop Processors with Radeon™ GraphicsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD EPYC™ 9004 Series Processorsversion=various
Advanced Micro Devices, Inc. · AMD EPYC™ 7001 Series Processorsversion=various
Advanced Micro Devices, Inc. · AMD Ryzen™ 7035 Series Processors with Radeon™ GraphicsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD EPYC 7002 Series Processorsversion=various
Advanced Micro Devices, Inc. · AMD Ryzen™ 3000 Series Mobile Processor with Radeon™ GraphicsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ Embedded R1000 Series ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ 3000 Series Desktop ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ 5000 Series Desktop ProcessorsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ 5000 Series Processors with Radeon™ GraphicsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD Ryzen™ 5000 Series Desktop Processor with Radeon™ GraphicsAffected versions are unavailable in this record.
Advanced Micro Devices, Inc. · AMD EPYC™ 7003 Series Processorsversion=various
Advanced Micro Devices, Inc. · AMD Ryzen™ 4000 Series Mobile Processors with Radeon™ GraphicsAffected versions are unavailable in this record.

Published CVSS scores

3.9Advanced Micro Devices, Inc.CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:N/I:L/A:L

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-863Incorrect Authorization
T1542.001Pre-OS Boot: System Firmware

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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