CVE-2022-4744

Local crash or privilege escalation via double free

Published Mar 30, 2023 · Updated Feb 14, 2025

Double-free in the Linux Kernel TUN/TAP driver 5.16-rc7 allows local users to crash the system or escalate privileges. When register_netdevice() fails, tun_free_netdev() frees dev->tstats and tun->security after the registration path has already released them. Creating a TUN/TAP device named "default" or "all" can trigger the failure, but device creation requires CAP_NET_ADMIN; successful exploitation can corrupt kernel memory, causing a crash or privilege escalation.

CVSS severity7.8
High
EPSS probability0.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Double-free in the Linux Kernel TUN/TAP driver 5.16-rc7 allows local users to crash the system or escalate privileges. When register_netdevice() fails, tun_free_netdev() frees dev->tstats and tun->security after the registration path has already released them. Creating a TUN/TAP device named "default" or "all" can trigger the failure, but device creation requires CAP_NET_ADMIN; successful exploitation can corrupt kernel memory, causing a crash or privilege escalation.

The record

CVE
CVE-2022-4744
Published
Mar 30, 2023
Updated
Feb 14, 2025
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-415, CWE-460, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 30, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 14, 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=Linux kernel 5.16-rc7

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=Linux kernel 5.16-rc7

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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-415Double Free
CWE-460Improper Cleanup on Thrown Exception
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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