CVE-2021-26362

Integrity and availability loss via malformed syscall

Published May 12, 2022 · Updated Sep 16, 2024

A system-management vulnerability in AMD Ryzen Series and AMD Athlon Series processors allows local users to compromise integrity and availability via malformed system calls. A malicious or compromised UApp or AGESA Boot Loader can send a malformed system call that maps sensitive System Management Network registers. Exploitation requires code running locally in the affected platform firmware environment and can corrupt protected register state or interrupt platform operation.

CVSS severity7.1
High
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A system-management vulnerability in AMD Ryzen Series and AMD Athlon Series processors allows local users to compromise integrity and availability via malformed system calls. A malicious or compromised UApp or AGESA Boot Loader can send a malformed system call that maps sensitive System Management Network registers. Exploitation requires code running locally in the affected platform firmware environment and can corrupt protected register state or interrupt platform operation.

The record

CVE
CVE-2021-26362
Published
May 12, 2022
Updated
Sep 16, 2024
Vendor
AMD
Product
AMD Ryzen Series
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 12, 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=various

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

AMD · AMD Ryzen Seriesversion=various
AMD · AMD Athlon Seriesversion=various

Published CVSS scores

7.1NVDCVSS: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.

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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

No sourced classifications are available.

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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