Linux Kernel up to 6.4.9 sysv sb_getblk null pointer dereference

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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.4.9. This affects the function sb_getblk of the component sysv. This manipulation causes null pointer dereference. This vulnerability is registered as CVE-2023-54264. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.4.9. Affected by this vulnerability is the function sb_getblk of the component sysv. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: fs/sysv: Null check to prevent null-ptr-deref bug sb_getblk(inode->i_sb, parent) return a null ptr and taking lock on that leads to the null-ptr-deref bug.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2023-54264 since 12/30/2025. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 281719 (Linux Distros Unpatched Vulnerability : CVE-2023-54264), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.14.322, 4.19.291, 5.4.253, 5.10.190, 5.15.126, 6.1.45 or 6.4.10 eliminates this vulnerability. Applying the patch e976988bc245ec3768cc0f76bed7d05488a7dd0f/baa60c66a310c50785289b0ede6fdce8ec3219c7/0a44ceba77c3267f8505dda102a59367dc24caee/7f740bc696d4617f8ee44565e8ac0d36278a1e91/afd9a31b5aa4b3747f382d44a7b03b7b5d0b7635/1416eebaad80bdc85ad9f97f27242011b031e2a9/e28f376dd8dfcc4e880ac101184132bc08703f6e/ea2b62f305893992156a798f665847e0663c9f41 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (281719) and CERT Bund (WID-SEC-2025-2941). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • IBM Power Hardware Management Console
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • Open Source Linux Kernel
  • RESF Rocky Linux
  • IBM DataPower Gateway

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.7
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 281719
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2023-54264

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 4.14.322/4.19.291/5.4.253/5.10.190/5.15.126/6.1.45/6.4.10
Patch: e976988bc245ec3768cc0f76bed7d05488a7dd0f/baa60c66a310c50785289b0ede6fdce8ec3219c7/0a44ceba77c3267f8505dda102a59367dc24caee/7f740bc696d4617f8ee44565e8ac0d36278a1e91/afd9a31b5aa4b3747f382d44a7b03b7b5d0b7635/1416eebaad80bdc85ad9f97f27242011b031e2a9/e28f376dd8dfcc4e880ac101184132bc08703f6e/ea2b62f305893992156a798f665847e0663c9f41

Timelineinfo

12/30/2025 Advisory disclosed
12/30/2025 +0 days CVE reserved
12/30/2025 +0 days VulDB entry created
04/27/2026 +118 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-54264 (🔒)
GCVE (CVE): GCVE-0-2023-54264
GCVE (VulDB): GCVE-100-338995
CERT Bund: WID-SEC-2025-2941 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 12/30/2025 16:58
Updated: 04/27/2026 06:14
Changes: 12/30/2025 16:58 (59), 01/01/2026 14:59 (7), 01/06/2026 00:37 (2), 04/27/2026 06:14 (1)
Complete: 🔍
Cache ID: 216::103

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