CVE-2021-46930

Kernel crash via uninitialized MTU3 request list

Published Feb 27, 2024 · Updated May 11, 2026

Use-after-free in the Linux kernel MTU3 USB gadget driver allows local users to crash the system during gadget shutdown. mtu3_alloc_request leaves mreq->list uninitialized, so mtu3_req_complete later treats stale pointers as a valid list entry during teardown. Reachability requires local access and an active MTU3 USB gadget configuration; the documented consequence is a kernel crash.

CVSS severity5.5
Medium
EPSS probability0.22%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in the Linux kernel MTU3 USB gadget driver allows local users to crash the system during gadget shutdown. mtu3_alloc_request leaves mreq->list uninitialized, so mtu3_req_complete later treats stale pointers as a valid list entry during teardown. Reachability requires local access and an active MTU3 USB gadget configuration; the documented consequence is a kernel crash.

The record

CVE
CVE-2021-46930
Published
Feb 27, 2024
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 27, 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=5.2
  2. Affected versionversion=83374e035b6286731c5aa617844c7b724294c2a7 <249ddfbe00570d6dc76208e88017937d4d374c79
  3. Affected versionversion=83374e035b6286731c5aa617844c7b724294c2a7 <3b6efe0b7ba03cc2acf0694b46d6ff33c5b4c295
  4. Affected versionversion=83374e035b6286731c5aa617844c7b724294c2a7 <585e2b244dda7ea733274e4b8fa27853d625d3bf
  5. Affected versionversion=83374e035b6286731c5aa617844c7b724294c2a7 <8c313e3bfd9adae8d5c4ba1cc696dcbc86fbf9bf

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.2; version=83374e035b6286731c5aa617844c7b724294c2a7 <249ddfbe00570d6dc76208e88017937d4d374c79; version=83374e035b6286731c5aa617844c7b724294c2a7 <3b6efe0b7ba03cc2acf0694b46d6ff33c5b4c295; version=83374e035b6286731c5aa617844c7b724294c2a7 <585e2b244dda7ea733274e4b8fa27853d625d3bf; version=83374e035b6286731c5aa617844c7b724294c2a7 <8c313e3bfd9adae8d5c4ba1cc696dcbc86fbf9bf

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

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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-416Use After Free
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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