CVE-2022-29581

Local root escalation via invalid netns reference release

Published May 17, 2022 · Updated Apr 21, 2025

Use-after-free in the u32 traffic classifier in Linux Kernel 4.14 through 5.17 allows local users to gain root privileges. The u32_change error path releases a network-namespace reference that was never acquired, freeing struct net while it remains reachable. Triggering the faulty classifier update requires local low-privileged access; successful exploitation grants root code execution, while failed attempts can crash the host.

CVSS severity7.8
High
EPSS probability0.93%
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 u32 traffic classifier in Linux Kernel 4.14 through 5.17 allows local users to gain root privileges. The u32_change error path releases a network-namespace reference that was never acquired, freeing struct net while it remains reachable. Triggering the faulty classifier update requires local low-privileged access; successful exploitation grants root code execution, while failed attempts can crash the host.

The record

CVE
CVE-2022-29581
Published
May 17, 2022
Updated
Apr 21, 2025
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-911, CWE-416, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 17, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 21, 2025Record 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=4.14 <unspecified
  2. Affected versionversion=unspecified <5.18

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=4.14 <unspecified; version=unspecified <5.18

Published CVSS scores

7.8SUSECVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.8National Vulnerability DatabaseCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.8UbuntuCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.2National Vulnerability DatabaseAV: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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-911Improper Update of Reference Count
CWE-416Use After Free
T1068Exploitation for Privilege Escalation

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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