CVE-2022-4127

System crash via missing io_uring file-table check

Published Nov 28, 2022 · Updated Apr 14, 2025

NULL pointer dereference in Linux kernel 5.19-rc1 through 5.19-rc5 allows local users to crash the system through an io_uring update. io_files_update_with_index_alloc honors IORING_FILE_INDEX_ALLOC and searches for a free bit without first checking whether req->ctx->file_data points to a file table. A local low-privileged user must submit the crafted fixed-file update, and triggering the dereference can interrupt the entire host.

CVSS severity5.5
Medium
EPSS probability0.21%
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 5.19-rc1 through 5.19-rc5 allows local users to crash the system through an io_uring update. io_files_update_with_index_alloc honors IORING_FILE_INDEX_ALLOC and searches for a free bit without first checking whether req->ctx->file_data points to a file table. A local low-privileged user must submit the crafted fixed-file update, and triggering the dereference can interrupt the entire host.

The record

CVE
CVE-2022-4127
Published
Nov 28, 2022
Updated
Apr 14, 2025
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-476, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Nov 28, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 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=Fixed in 5.19

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=Fixed in 5.19

Published CVSS scores

5.5CISA-ADPCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5SUSECVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5NIST NVDCVSS: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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
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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