CVE-2018-9439

Kernel privilege escalation via packet hook race

Published Dec 4, 2024 · Updated Dec 5, 2024

Use-after-free in the Android kernel network stack allows local users with System execution privileges to gain kernel privileges. Improper locking between __unregister_prot_hook and packet_release in af_packet.c permits packet state to be freed while it remains in use. The flaw needs no user interaction, but existing System-level local code execution is required to reach the further kernel compromise.

CVSS severity6.7
Medium
EPSS probability0.08%
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 Android kernel network stack allows local users with System execution privileges to gain kernel privileges. Improper locking between __unregister_prot_hook and packet_release in af_packet.c permits packet state to be freed while it remains in use. The flaw needs no user interaction, but existing System-level local code execution is required to reach the further kernel compromise.

The record

CVE
CVE-2018-9439
Published
Dec 4, 2024
Updated
Dec 5, 2024
Vendor
Google
Product
Google Pixel
Classifications
CWE-416, T1068
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Dec 4, 2024CVE publishedPublication date reported by the CVE source.
  2. Dec 5, 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=0 <2018-08-05

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Google · Google Pixelversion=0 <2018-08-05
Google · Androidversion=0 <2018-08-05; version=Kernel

Published CVSS scores

6.7NVDCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
7.8CISA-ADPCVSS: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.

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

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

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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