CVE-2023-53421

Advisory lineage Upstream: 0 Downstream: 31
Modified
Published: 18 Sept 2025, 16:04
Last modified:01 Jun 2026, 16:04

Vulnerability Summary

Overall Risk (default)
low
22/100
CVSS Score
5.5 MEDIUM
v3.1 (cve.org)
EPSS Score
0.03% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

18 Sept 2025, 16:04
Published
Vulnerability first disclosed
01 Jun 2026, 16:04
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: Reinit blkg_iostat_set after clearing in blkcg_reset_stats() When blkg_alloc() is called to allocate a blkcg_gq structure with the associated blkg_iostat_set's, there are 2 fields within blkg_iostat_set that requires proper initialization - blkg & sync. The former field was introduced by commit 3b8cc6298724 ("blk-cgroup: Optimize blkcg_rstat_flush()") while the later one was introduced by commit f73316482977 ("blk-cgroup: reimplement basic IO stats using cgroup rstat"). Unfortunately those fields in the blkg_iostat_set's are not properly re-initialized when they are cleared in v1's blkcg_reset_stats(). This can lead to a kernel panic due to NULL pointer access of the blkg pointer. The missing initialization of sync is less problematic and can be a problem in a debug kernel due to missing lockdep initialization. Fix these problems by re-initializing them after memory clearing.

CVSS Metrics

  • v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.03%• Percentile: 8%

Techniques & Countermeasures

  • CWE-476•NULL Pointer Dereference

    The product dereferences a pointer that it expects to be valid but is NULL.

Affected Systems

  • linux•linux

    ≥ f73316482977ac401ac37245c9df48079d4e11f3, < 58c135513562698f222a58ba07dbdfcfb268aa0d | ≥ f73316482977ac401ac37245c9df48079d4e11f3, < 0561aa6033dd181594116d705c41fc16e97161a2 | ≥ f73316482977ac401ac37245c9df48079d4e11f3, < 892faa76be894d324bf48b12a55c7af7be2bad83 | ≥ f73316482977ac401ac37245c9df48079d4e11f3, < b0d26283af612b9e0cc3188b0b88ad7fdea447e8 | ≥ f73316482977ac401ac37245c9df48079d4e11f3, < abbce7f82613ea5eeefd0fc3c1c8e449b9cef2a2 | ≥ f73316482977ac401ac37245c9df48079d4e11f3, < 3d2af77e31ade05ff7ccc3658c3635ec1bea0979 | 5.5

  • linux•linux_kernel

    ≥ 5.5, < 6.3.13 | ≥ 6.4, < 6.4.4

References (6)