CVE-2021-26372

Denial of service via PCIE bounds check

Published May 11, 2022 · Updated Sep 16, 2024

Insufficient bounds checking in AMD Ryzen Processors of various versions allows local authenticated users to cause denial of service through the SMU PCIE Hot Plug Config Table. The SMU table accepts out-of-range values and accesses invalid address space, which can stop processor service. The same condition is reported for AMD EPYC and Athlon processor families; exploitation requires local authenticated access to the relevant platform interface and can interrupt availability without reported confidentiality or integrity impact.

CVSS severity5.5
Medium
EPSS probability0.22%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Insufficient bounds checking in AMD Ryzen Processors of various versions allows local authenticated users to cause denial of service through the SMU PCIE Hot Plug Config Table. The SMU table accepts out-of-range values and accesses invalid address space, which can stop processor service. The same condition is reported for AMD EPYC and Athlon processor families; exploitation requires local authenticated access to the relevant platform interface and can interrupt availability without reported confidentiality or integrity impact.

The record

CVE
CVE-2021-26372
Published
May 11, 2022
Updated
Sep 16, 2024
Vendor
AMD
Product
AMD EPYC Processors
Classifications
T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 11, 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

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

Is a vulnerable build present?

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

  1. Affected versionversion=various

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

AMD · AMD EPYC Processorsversion=various
AMD · AMD Athlon Processorsversion=various
AMD · AMD Ryzen Processorsversion=various

Published CVSS scores

4.9NVDAV:L/AC:L/Au:N/C:N/I:N/A:C
5.5NVDCVSS:3.1/AV:L/AC:L/PR:L/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
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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo