CVE-2026-31481

Kernel crash via undrained deferred trigger frees

Published Apr 22, 2026 · Updated Apr 22, 2026

NULL pointer dereference in Linux Kernel 6.19 allows local users to crash the system through duplicate boot-time trace triggers. If cleanup-kthread creation fails, trigger_data_free_list retains deferred nodes because the fallback frees only the current trigger instead of draining the queue. Exploitation requires root or CAP_SYS_ADMIN access to configure the kernel command line; the second identical traceon trigger dereferences a null pointer.

CVSS severity5.5
Medium
EPSS probability0.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in Linux Kernel 6.19 allows local users to crash the system through duplicate boot-time trace triggers. If cleanup-kthread creation fails, trigger_data_free_list retains deferred nodes because the fallback frees only the current trigger instead of draining the queue. Exploitation requires root or CAP_SYS_ADMIN access to configure the kernel command line; the second identical traceon trigger dereferences a null pointer.

The record

CVE
CVE-2026-31481
Published
Apr 22, 2026
Updated
Apr 22, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-476, T1499
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Apr 22, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 22, 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=6.19
  2. Affected versionversion=61d445af0a7c70018111919e47beaaee15653f2f <250ab25391edeeab8462b68be42e4904506c409c
  3. Affected versionversion=61d445af0a7c70018111919e47beaaee15653f2f <771624b7884a83bb9f922ae64ee41a5f8b7576c9

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linux Kernelversion=6.19; version=61d445af0a7c70018111919e47beaaee15653f2f <250ab25391edeeab8462b68be42e4904506c409c; version=61d445af0a7c70018111919e47beaaee15653f2f <771624b7884a83bb9f922ae64ee41a5f8b7576c9

Published CVSS scores

5.5NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5CanonicalCVSS:3.1/AV:L/AC:L/PR:L/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.

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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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499Endpoint Denial of Service

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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