Linux Kernel up to 6.2.10 nilfs_sysfs_create_device_group use after free

CVSS Meta Temp Score
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CTI Interest Score
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6.6$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.2.10. It has been rated as critical. The impacted element is the function nilfs_sysfs_create_device_group. The manipulation leads to use after free. This vulnerability is uniquely identified as CVE-2023-53440. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.2.10. This issue affects the function nilfs_sysfs_create_device_group. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix sysfs interface lifetime The current nilfs2 sysfs support has issues with the timing of creation and deletion of sysfs entries, potentially leading to null pointer dereferences, use-after-free, and lockdep warnings. Some of the sysfs attributes for nilfs2 per-filesystem instance refer to metadata file "cpfile", "sufile", or "dat", but nilfs_sysfs_create_device_group that creates those attributes is executed before the inodes for these metadata files are loaded, and nilfs_sysfs_delete_device_group which deletes these sysfs entries is called after releasing their metadata file inodes. Therefore, access to some of these sysfs attributes may occur outside of the lifetime of these metadata files, resulting in inode NULL pointer dereferences or use-after-free. In addition, the call to nilfs_sysfs_create_device_group() is made during the locking period of the semaphore "ns_sem" of nilfs object, so the shrinker call caused by the memory allocation for the sysfs entries, may derive lock dependencies "ns_sem" -> (shrinker) -> "locks acquired in nilfs_evict_inode()". Since nilfs2 may acquire "ns_sem" deep in the call stack holding other locks via its error handler __nilfs_error(), this causes lockdep to report circular locking. This is a false positive and no circular locking actually occurs as no inodes exist yet when nilfs_sysfs_create_device_group() is called. Fortunately, the lockdep warnings can be resolved by simply moving the call to nilfs_sysfs_create_device_group() out of "ns_sem". This fixes these sysfs issues by revising where the device's sysfs interface is created/deleted and keeping its lifetime within the lifetime of the metadata files above.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2023-53440 since 09/17/2025. The exploitation is known to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 12/12/2025).

The vulnerability scanner Nessus provides a plugin with the ID 265907 (Linux Distros Unpatched Vulnerability : CVE-2023-53440), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.14.313, 4.19.281, 5.4.241, 5.10.178, 5.15.107, 6.1.24 or 6.2.11 eliminates this vulnerability. Applying the patch d20dcec8f326deb77b6688f8441e014045dac457/5fe0ea141fbb887d407f1bf572ebf24427480d5c/83b16a60e413148685739635901937e2f16a7873/3dbee84bf9e3273c4bb9ca6fc18ff22fba23dd24/d540aea451ab5489777a8156560f1388449b3109/1942ccb7d95f287a312fcbabfa8bc9ba501b1953/daf4eb3a908b108279b60172d2f176e70d2df875/42560f9c92cc43dce75dbf06cc0d840dced39b12 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 (265907) and CERT Bund (WID-SEC-2025-2092). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source Linux Kernel
  • Dell Secure Connect Gateway
  • IBM QRadar SIEM

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.6

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 265907
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2023-53440

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 4.14.313/4.19.281/5.4.241/5.10.178/5.15.107/6.1.24/6.2.11
Patch: d20dcec8f326deb77b6688f8441e014045dac457/5fe0ea141fbb887d407f1bf572ebf24427480d5c/83b16a60e413148685739635901937e2f16a7873/3dbee84bf9e3273c4bb9ca6fc18ff22fba23dd24/d540aea451ab5489777a8156560f1388449b3109/1942ccb7d95f287a312fcbabfa8bc9ba501b1953/daf4eb3a908b108279b60172d2f176e70d2df875/42560f9c92cc43dce75dbf06cc0d840dced39b12

Timelineinfo

09/17/2025 CVE reserved
09/18/2025 +1 days Advisory disclosed
09/18/2025 +0 days VulDB entry created
12/12/2025 +85 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-53440 (🔒)
GCVE (CVE): GCVE-0-2023-53440
GCVE (VulDB): GCVE-100-324947
CERT Bund: WID-SEC-2025-2092 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 09/18/2025 19:25
Updated: 12/12/2025 01:00
Changes: 09/18/2025 19:25 (58), 09/20/2025 20:01 (7), 09/26/2025 07:05 (2), 11/29/2025 19:33 (1), 12/12/2025 01:00 (11)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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