CVE-2023-53421

Aliases:UBUNTU-CVE-2023-53421DEBIAN-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
0.16% LOW
0% probability +0.14%
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: 0.16%• Percentile: 6%

Techniques & Countermeasures

  • CWE-476•NULL Pointer Dereference

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

Affected Systems

  • debian•linux

    < 5.10.259-1 | < 6.1.162-1 | < 6.4.4-1 | < 6.4.4-1

  • debian•linux-6.1

    < 6.1.162-1~deb11u1

  • ubuntu•linux

    < 5.15.0-176.186

  • ubuntu•linux-allwinner-5.19

    all

  • ubuntu•linux-aws

    < 5.15.0-1105.112

  • ubuntu•linux-aws-5.0

    all

  • ubuntu•linux-aws-5.11

    all

  • ubuntu•linux-aws-5.13

    all

  • ubuntu•linux-aws-5.15

    < 5.15.0-1105.112~20.04.1

  • ubuntu•linux-aws-5.19

    all

  • ubuntu•linux-aws-5.3

    all

  • ubuntu•linux-aws-5.8

    all

  • ubuntu•linux-aws-6.2

    all

  • ubuntu•linux-aws-6.5

    all

  • ubuntu•linux-aws-fips

    all | < 5.15.0-1105.112+fips1

  • ubuntu•linux-azure

    all | < 5.15.0-1110.119

  • ubuntu•linux-azure-5.11

    all

  • ubuntu•linux-azure-5.13

    all

  • ubuntu•linux-azure-5.15

    < 5.15.0-1110.119~20.04.1

  • ubuntu•linux-azure-5.19

    all

  • ubuntu•linux-azure-5.3

    all

  • ubuntu•linux-azure-5.8

    all

  • ubuntu•linux-azure-6.11

    all

  • ubuntu•linux-azure-6.2

    all

  • ubuntu•linux-azure-6.5

    all

  • ubuntu•linux-azure-edge

    all

  • ubuntu•linux-azure-fde

    all | all

  • ubuntu•linux-azure-fde-5.19

    all

  • ubuntu•linux-azure-fde-6.2

    all

  • ubuntu•linux-azure-fips

    all | < 5.15.0-1110.119+fips1

  • ubuntu•linux-bluefield

    all | < 5.15.0-1089.91

  • ubuntu•linux-fips

    all | < 5.15.0-176.186+fips1

  • ubuntu•linux-gcp

    all | < 5.15.0-1105.114

  • ubuntu•linux-gcp-5.11

    all

  • ubuntu•linux-gcp-5.13

    all

  • ubuntu•linux-gcp-5.15

    < 5.15.0-1106.115~20.04.1

  • ubuntu•linux-gcp-5.19

    all

  • ubuntu•linux-gcp-5.3

    all

  • ubuntu•linux-gcp-5.8

    all

  • ubuntu•linux-gcp-6.11

    all

  • ubuntu•linux-gcp-6.2

    all

  • ubuntu•linux-gcp-6.5

    all

  • ubuntu•linux-gcp-fips

    all | < 5.15.0-1105.114+fips1

  • ubuntu•linux-gke

    all | < 5.15.0-1101.107

  • ubuntu•linux-gke-4.15

    all

  • ubuntu•linux-gke-5.15

    all

  • ubuntu•linux-gke-5.4

    all

  • ubuntu•linux-gkeop

    all | < 5.15.0-1088.96

  • ubuntu•linux-gkeop-5.15

    all

  • ubuntu•linux-gkeop-5.4

    all

Showing first 50 affected entries in server-rendered view.

References (23)