CVE-2021-47331

Kernel crash via premature USB interrupt registration

Published May 21, 2024 · Updated May 11, 2026

A NULL pointer dereference in affected Linux kernel releases allows local users to crash the system during startup with an OTG cable. The usb-conn-gpio probe path requests IDDIG/VBUS interrupts before registering the charger power supply, so an early IDDIG interrupt dereferences a still-NULL charger pointer. Triggering requires the GPIO USB connector driver, attached OTG hardware, and a power-on event; the documented consequence is a kernel crash.

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

A NULL pointer dereference in affected Linux kernel releases allows local users to crash the system during startup with an OTG cable. The usb-conn-gpio probe path requests IDDIG/VBUS interrupts before registering the charger power supply, so an early IDDIG interrupt dereferences a still-NULL charger pointer. Triggering requires the GPIO USB connector driver, attached OTG hardware, and a power-on event; the documented consequence is a kernel crash.

The record

CVE
CVE-2021-47331
Published
May 21, 2024
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-476, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 21, 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=5.9
  2. Affected versionversion=e3ee0e740c3887d2293e8d54a8707218d70d86ca <1a133a0996d6b4c83509d570ed4edcba34c44f25
  3. Affected versionversion=e3ee0e740c3887d2293e8d54a8707218d70d86ca <436906fd248e018403bcda61a9311d9af02912f1
  4. Affected versionversion=e3ee0e740c3887d2293e8d54a8707218d70d86ca <880287910b1892ed2cb38977893b947382a09d21
  5. Affected versionversion=e3ee0e740c3887d2293e8d54a8707218d70d86ca <8e8d910e9a3a7fba86140aff4924c30955ab228b

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.9; version=e3ee0e740c3887d2293e8d54a8707218d70d86ca <1a133a0996d6b4c83509d570ed4edcba34c44f25; version=e3ee0e740c3887d2293e8d54a8707218d70d86ca <436906fd248e018403bcda61a9311d9af02912f1; version=e3ee0e740c3887d2293e8d54a8707218d70d86ca <880287910b1892ed2cb38977893b947382a09d21; version=e3ee0e740c3887d2293e8d54a8707218d70d86ca <8e8d910e9a3a7fba86140aff4924c30955ab228b

Published CVSS scores

5.5NIST NVDCVSS: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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
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

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Your stack

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