CVE-2021-4210

Local code execution via unvalidated SMI input

Published Apr 22, 2022 · Updated Aug 3, 2024

Improper input validation in Lenovo BIOS NVMe drivers allows local users with elevated privileges to execute arbitrary code. The affected SMI callback fails to adequately validate input before the firmware driver processes it; Lenovo has not disclosed the callback's input fields or exact validation failure. Exploitation requires local access and elevated privileges, and the published record reports code execution without a remote attack path.

CVSS severity6.7
Medium
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Lenovo BIOS NVMe drivers allows local users with elevated privileges to execute arbitrary code. The affected SMI callback fails to adequately validate input before the firmware driver processes it; Lenovo has not disclosed the callback's input fields or exact validation failure. Exploitation requires local access and elevated privileges, and the published record reports code execution without a remote attack path.

The record

CVE
CVE-2021-4210
Published
Apr 22, 2022
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-20, T1068
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Apr 22, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.7Lenovo Group Ltd.CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
7.2NIST NVDAV:L/AC:L/Au:N/C:C/I:C/A:C

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-20Improper Input Validation
T1068Exploitation for Privilege Escalation

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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