CVE-2023-53440

MEDIUM EPSS 3.1%
Published Sep 18, 20259mo ago · Modified Jun 17, 20261w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Sep 18, 2025 9mo ago
Last Modified Jun 17, 2026 1w ago

Description

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.

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
3.1% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-476 NULL Pointer Dereference Memory Safety

Affected Products 12

VendorProductVersionRange
linuxlinux_kernel*≥3.17  –  <4.14.313
linuxlinux_kernel*≥4.15  –  <4.19.281
linuxlinux_kernel*≥4.20  –  <5.4.241
linuxlinux_kernel*≥5.5  –  <5.10.178
linuxlinux_kernel*≥5.11  –  <5.15.107
linuxlinux_kernel*≥5.16  –  <6.1.24
linuxlinux_kernel*≥6.2  –  <6.2.11
linuxlinux_kernel6.3any
linuxlinux_kernel6.3any
linuxlinux_kernel6.3any
linuxlinux_kernel6.3any
linuxlinux_kernel6.3any

References 8

  • git.kernel.org https://git.kernel.org/stable/c/1942ccb7d95f287a312fcbabfa8bc9ba501b1953
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/3dbee84bf9e3273c4bb9ca6fc18ff22fba23dd24
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/42560f9c92cc43dce75dbf06cc0d840dced39b12
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5fe0ea141fbb887d407f1bf572ebf24427480d5c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/83b16a60e413148685739635901937e2f16a7873
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/d20dcec8f326deb77b6688f8441e014045dac457
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/d540aea451ab5489777a8156560f1388449b3109
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/daf4eb3a908b108279b60172d2f176e70d2df875
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/1942ccb7d95f287a312fcbabfa8bc9ba501b1953
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/3dbee84bf9e3273c4bb9ca6fc18ff22fba23dd24
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/42560f9c92cc43dce75dbf06cc0d840dced39b12
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5fe0ea141fbb887d407f1bf572ebf24427480d5c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/83b16a60e413148685739635901937e2f16a7873
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/d20dcec8f326deb77b6688f8441e014045dac457
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/d540aea451ab5489777a8156560f1388449b3109
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/daf4eb3a908b108279b60172d2f176e70d2df875
    Patch