{"cve":"CVE-2023-53421","nvd":{"published":"2025-09-18T16:15:45.897","modified":"2026-06-17T06:45:17.053","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nblk-cgroup: Reinit blkg_iostat_set after clearing in blkcg_reset_stats()\n\nWhen blkg_alloc() is called to allocate a blkcg_gq structure\nwith the associated blkg_iostat_set's, there are 2 fields within\nblkg_iostat_set that requires proper initialization - blkg & sync.\nThe former field was introduced by commit 3b8cc6298724 (\"blk-cgroup:\nOptimize blkcg_rstat_flush()\") while the later one was introduced by\ncommit f73316482977 (\"blk-cgroup: reimplement basic IO stats using\ncgroup rstat\").\n\nUnfortunately those fields in the blkg_iostat_set's are not properly\nre-initialized when they are cleared in v1's blkcg_reset_stats(). This\ncan lead to a kernel panic due to NULL pointer access of the blkg\npointer. The missing initialization of sync is less problematic and\ncan be a problem in a debug kernel due to missing lockdep initialization.\n\nFix these problems by re-initializing them after memory clearing.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/0561aa6033dd181594116d705c41fc16e97161a2","https://git.kernel.org/stable/c/3d2af77e31ade05ff7ccc3658c3635ec1bea0979","https://git.kernel.org/stable/c/58c135513562698f222a58ba07dbdfcfb268aa0d","https://git.kernel.org/stable/c/892faa76be894d324bf48b12a55c7af7be2bad83","https://git.kernel.org/stable/c/abbce7f82613ea5eeefd0fc3c1c8e449b9cef2a2"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:10:08.713834912+00:00"},"epss":{"cve":"CVE-2023-53421","score":0.00165,"percentile":0.05697,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}