CVE-2023-53576Public exploit

Local kernel crash via invalid null_blk queue mode

Published Oct 4, 2025 · Updated Oct 4, 2025

NULL pointer dereference in the Linux kernel null_blk driver allows local users to crash the kernel through configfs. null_validate_conf accepts the unsupported NULL_Q_RQ queue mode, so null_add_dev later dereferences an uninitialized request-queue pointer when power is enabled. The null_blk module must be loaded, and the user must be able to create and configure a null_blk device through configfs; triggering the flaw causes a kernel oops.

CVSS severity5.5
Medium
EPSS probability0.14%
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 the Linux kernel null_blk driver allows local users to crash the kernel through configfs. null_validate_conf accepts the unsupported NULL_Q_RQ queue mode, so null_add_dev later dereferences an uninitialized request-queue pointer when power is enabled. The null_blk module must be loaded, and the user must be able to create and configure a null_blk device through configfs; triggering the flaw causes a kernel oops.

The record

CVE
CVE-2023-53576
Published
Oct 4, 2025
Updated
Oct 4, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-476, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 4, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 4, 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=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <35e304dbcefa95237a3d6f94c007bfb10f012b17
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <63f8793ee60513a09f110ea460a6ff2c33811cdb
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <651260e563d9f50827dac496dc8a0b9b23d5db1a
  4. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <e732a266b973cd4e115e2cc2ea5007119e8a7fbc
  5. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <fd35b7bb6d5a329c427924886949ab51f210200a

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <35e304dbcefa95237a3d6f94c007bfb10f012b17; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <63f8793ee60513a09f110ea460a6ff2c33811cdb; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <651260e563d9f50827dac496dc8a0b9b23d5db1a; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <e732a266b973cd4e115e2cc2ea5007119e8a7fbc; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <fd35b7bb6d5a329c427924886949ab51f210200a

Published CVSS scores

5.5NVDCVSS: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 exploitPublished

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499.004Application or System Exploitation

Public exploit references

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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