cbcvebase.
CVE-2023-53421
published 2025-09-18

CVE-2023-53421: 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()…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.15%
4.7th percentile
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.

Affected

36 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.162-1 (bookworm)linux 6.1.162-1 (bookworm)
debianlinux-6.1< linux 6.1.162-1 (bookworm)linux 6.1.162-1 (bookworm)
linuxlinux
linuxlinux>= f73316482977ac401ac37245c9df48079d4e11f3 < 58c135513562698f222a58ba07dbdfcfb268aa0d58c135513562698f222a58ba07dbdfcfb268aa0d
linuxlinux>= f73316482977ac401ac37245c9df48079d4e11f3 < 0561aa6033dd181594116d705c41fc16e97161a20561aa6033dd181594116d705c41fc16e97161a2
linuxlinux>= f73316482977ac401ac37245c9df48079d4e11f3 < 892faa76be894d324bf48b12a55c7af7be2bad83892faa76be894d324bf48b12a55c7af7be2bad83
linuxlinux>= f73316482977ac401ac37245c9df48079d4e11f3 < b0d26283af612b9e0cc3188b0b88ad7fdea447e8b0d26283af612b9e0cc3188b0b88ad7fdea447e8
linuxlinux>= f73316482977ac401ac37245c9df48079d4e11f3 < abbce7f82613ea5eeefd0fc3c1c8e449b9cef2a2abbce7f82613ea5eeefd0fc3c1c8e449b9cef2a2
linuxlinux>= f73316482977ac401ac37245c9df48079d4e11f3 < 3d2af77e31ade05ff7ccc3658c3635ec1bea09793d2af77e31ade05ff7ccc3658c3635ec1bea0979
linuxlinux_kernel>= 0 < 6.1.162-16.1.162-1
linuxlinux_kernel>= 0 < 6.4.4-16.4.4-1
linuxlinux_kernel>= 0 < 6.4.4-16.4.4-1
linuxlinux_kernel>= 5.5 < 6.3.136.3.13
linuxlinux_kernel>= 6.4 < 6.4.46.4.4
msrccbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.202.1-1_on_cbl_mariner_2.0
ubuntulinux-azure
ubuntulinux-azure-5.15
ubuntulinux-azure-fips
ubuntulinux-fips
ubuntulinux-gcp-5.15
ubuntulinux-gcp-fips
ubuntulinux-hwe-5.15
ubuntulinux-ibm

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_ubuntu7.8HIGH
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.