CVE-2026-90066Hinoki check available

Kernel crash via unchecked thread error pointer

Published Sep 17, 2026 · Updated Sep 17, 2026

Null-pointer dereference in Linux ftrace samples allows local users to trigger a kernel crash via module unloading. In ftrace-direct-multi-modify, ftrace_direct_multi_init() stores kthread_run() failure as an unchecked error pointer, which ftrace_direct_multi_exit() passes to kthread_stop(). The crash requires privileged module loading and unloading after thread creation fails with an out-of-memory error; no data disclosure or arbitrary code execution is established.

CVSS severity4.1
Medium
EPSS probability0.20%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Null-pointer dereference in Linux ftrace samples allows local users to trigger a kernel crash via module unloading. In ftrace-direct-multi-modify, ftrace_direct_multi_init() stores kthread_run() failure as an unchecked error pointer, which ftrace_direct_multi_exit() passes to kthread_stop(). The crash requires privileged module loading and unloading after thread creation fails with an out-of-memory error; no data disclosure or arbitrary code execution is established.

The record

CVE
CVE-2026-90066
Published
Sep 17, 2026
Updated
Sep 17, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Sep 17, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 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=5.16
  2. Affected versionversion=e1067a07cfbc5a36abad3752fafe4c79e06db1bb <626614df9080d7052fbe24dc90b5434717ab7a9f
  3. Affected versionversion=e1067a07cfbc5a36abad3752fafe4c79e06db1bb <6727b7618f49401acf373fa3ec5712e2ec52e5cf
  4. Affected versionversion=e1067a07cfbc5a36abad3752fafe4c79e06db1bb <7a96b9f6d5ba23dbce66c8a4a242effd4c01a830
  5. Affected versionversion=e1067a07cfbc5a36abad3752fafe4c79e06db1bb <98b7b2a29ae87937aa02ab9391543ef8c602cd94
  6. Affected versionversion=e1067a07cfbc5a36abad3752fafe4c79e06db1bb <cf839636911d8313f3ecd098329fd0b96499e4cf

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linuxversion=5.16; version=e1067a07cfbc5a36abad3752fafe4c79e06db1bb <626614df9080d7052fbe24dc90b5434717ab7a9f; version=e1067a07cfbc5a36abad3752fafe4c79e06db1bb <6727b7618f49401acf373fa3ec5712e2ec52e5cf; version=e1067a07cfbc5a36abad3752fafe4c79e06db1bb <7a96b9f6d5ba23dbce66c8a4a242effd4c01a830; version=e1067a07cfbc5a36abad3752fafe4c79e06db1bb <98b7b2a29ae87937aa02ab9391543ef8c602cd94; version=e1067a07cfbc5a36abad3752fafe4c79e06db1bb <cf839636911d8313f3ecd098329fd0b96499e4cf

Published CVSS scores

4.1Amazon LinuxCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
4.1SUSECVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

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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