CVE-2021-47405

Service interruption via unreleased USB HID reports

Published May 21, 2024 · Updated May 11, 2026

Memory leak in affected Linux kernel releases allows local users to exhaust memory by removing a USB HID device with queued raw reports. The usbhid_stop function tears down a removed device without freeing unsent raw_report buffers retained by the USB HID driver. Repeatedly reaching this device-removal path consumes kernel memory and can interrupt service; exploitation requires local low-privileged access and control of a USB HID device.

CVSS severity5.5
Medium
EPSS probability0.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory leak in affected Linux kernel releases allows local users to exhaust memory by removing a USB HID device with queued raw reports. The usbhid_stop function tears down a removed device without freeing unsent raw_report buffers retained by the USB HID driver. Repeatedly reaching this device-removal path consumes kernel memory and can interrupt service; exploitation requires local low-privileged access and control of a USB HID device.

The record

CVE
CVE-2021-47405
Published
May 21, 2024
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-401, 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=2.6.28
  2. Affected versionversion=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <2b704864c92dcec2b295f276fcfbfb81d9831f81
  3. Affected versionversion=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <764ac04de056801dfe52a716da63f6e7018e7f3b
  4. Affected versionversion=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <7ce4e49146612261265671b1d30d117139021030
  5. Affected versionversion=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <965147067fa1bedff3ae1f07ce3f89f1a14d2df3
  6. Affected versionversion=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <c3156fea4d8a0e643625dff69a0421e872d1fdae
  7. Affected versionversion=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <efc5c8d29256955cc90d8d570849b2d6121ed09f
  8. Affected versionversion=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <f7744fa16b96da57187dc8e5634152d3b63d72de
  9. Affected versionversion=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <f7ac4d24e1610b92689946fa88177673f1e88a3f

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2.6.28; version=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <2b704864c92dcec2b295f276fcfbfb81d9831f81; version=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <764ac04de056801dfe52a716da63f6e7018e7f3b; version=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <7ce4e49146612261265671b1d30d117139021030; version=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <965147067fa1bedff3ae1f07ce3f89f1a14d2df3; version=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <c3156fea4d8a0e643625dff69a0421e872d1fdae; version=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <efc5c8d29256955cc90d8d570849b2d6121ed09f; version=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <f7744fa16b96da57187dc8e5634152d3b63d72de; version=f129ea6d1efe0eddcbb1f0faaec5623788ad9e58 <f7ac4d24e1610b92689946fa88177673f1e88a3f

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5Canonical UbuntuCVSS: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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime
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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