CVE-2021-47073

Local kernel oops via unconditional driver unregistration

Published Mar 1, 2024 · Updated May 11, 2026

Incorrect driver unregistration in Linux 4.15 through 5.13-rc2 allows local users to trigger a kernel oops when unloading dell_smbios. exit_dell_smbios_wmi() calls driver_unregister() even when init_dell_smbios_wmi() skipped registration because Dell WMI support was absent. Reaching the defect requires local permission to unload the module; the published result is an oops affecting availability, with no reported data access or code execution.

CVSS severity5.5
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect driver unregistration in Linux 4.15 through 5.13-rc2 allows local users to trigger a kernel oops when unloading dell_smbios. exit_dell_smbios_wmi() calls driver_unregister() even when init_dell_smbios_wmi() skipped registration because Dell WMI support was absent. Reaching the defect requires local permission to unload the module; the published result is an oops affecting availability, with no reported data access or code execution.

The record

CVE
CVE-2021-47073
Published
Mar 1, 2024
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Mar 1, 2024CVE publishedPublication date reported by the CVE source.
  2. May 11, 2026Record 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=1a258e670434f404a4500b65ba1afea2c2b29bba <0cf036a0d325200e6c27b90908e51195bbc557b1
  2. Affected versionversion=1a258e670434f404a4500b65ba1afea2c2b29bba <3a53587423d25c87af4b4126a806a0575104b45e
  3. Affected versionversion=1a258e670434f404a4500b65ba1afea2c2b29bba <6fa78a6b9a3beb676a010dc489c1257f7e432525
  4. Affected versionversion=1a258e670434f404a4500b65ba1afea2c2b29bba <75cfc833da4a2111106d4c134e93e0c7f41e35e7
  5. Affected versionversion=1a258e670434f404a4500b65ba1afea2c2b29bba <8d746ea7c687bab060a2c05a35c449302406cd52
  6. Affected versionversion=4.15

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linuxversion=1a258e670434f404a4500b65ba1afea2c2b29bba <0cf036a0d325200e6c27b90908e51195bbc557b1; version=1a258e670434f404a4500b65ba1afea2c2b29bba <3a53587423d25c87af4b4126a806a0575104b45e; version=1a258e670434f404a4500b65ba1afea2c2b29bba <6fa78a6b9a3beb676a010dc489c1257f7e432525; version=1a258e670434f404a4500b65ba1afea2c2b29bba <75cfc833da4a2111106d4c134e93e0c7f41e35e7; version=1a258e670434f404a4500b65ba1afea2c2b29bba <8d746ea7c687bab060a2c05a35c449302406cd52; version=4.15

Published CVSS scores

2.3OracleCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L
5.5CanonicalCVSS: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.

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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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

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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