CVE-2022-0646Public exploit

Local privilege escalation via post-unregister work cancellation

Published Feb 18, 2022 · Updated Aug 2, 2024

Use after free in the Linux Kernel MCTP serial driver in 5.17-rc1 through 5.17-rc5 allows local users to crash or escalate privileges. When mctp_serial_close unregisters its network device, it frees the shared allocation before cancel_work_sync accesses tx_work through the stale private pointer. Reaching the flaw requires an enabled MCTP serial driver and local TTY access; the demonstrated result is a kernel crash, while the CVE also reports privilege escalation.

CVSS severity7.8
High
EPSS probability0.34%
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 MCTP serial driver in 5.17-rc1 through 5.17-rc5 allows local users to crash or escalate privileges. When mctp_serial_close unregisters its network device, it frees the shared allocation before cancel_work_sync accesses tx_work through the stale private pointer. Reaching the flaw requires an enabled MCTP serial driver and local TTY access; the demonstrated result is a kernel crash, while the CVE also reports privilege escalation.

The record

CVE
CVE-2022-0646
Published
Feb 18, 2022
Updated
Aug 2, 2024
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-416, CWE-459, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 18, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5.17-rc5

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=5.17-rc5

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/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.

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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 exploitPublished

Weakness, pattern, technique

CWE-416Use After Free
CWE-459Incomplete Cleanup
T1068Exploitation for Privilege Escalation

Public exploit references

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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