{"id":"CVE-2023-54107","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nblk-cgroup: dropping parent refcount after pd_free_fn() is done\n\nSome cgroup policies will access parent pd through child pd even\nafter pd_offline_fn() is done","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nblk-cgroup: dropping parent refcount after pd_free_fn() is done\n\nSome cgroup policies will access parent pd through child pd even\nafter pd_offline_fn() is done. If pd_f…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-416"],"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 6","enterprise_linux 7","enterprise_linux 8","enterprise_linux 9"],"published":"2025-12-24","updated":"2026-10-15","sourceUpdated":"2026-10-15T22:17:53.140","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2023-54107","references":[{"url":"https://git.kernel.org/stable/c/c7241babf0855d8a6180cd1743ff0ec34de40b4e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-54107.json"},{"url":"https://access.redhat.com/security/cve/CVE-2023-54107"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2425208"},{"url":"https://www.cve.org/CVERecord?id=CVE-2023-54107"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-54107"},{"url":"https://lore.kernel.org/linux-cve-announce/2025122412-CVE-2023-54107-12ef@gregkh/T"}],"tags":["nvd","csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00152,"epssPercentile":0.04282,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-15T21:38:32.237187Z"},"scores":{"nvd":7.8,"vendor":5.8,"cna":7.8},"ingestedAt":"2026-10-15T22:48:25.429Z","slug":"CVE-2023-54107","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nblk-cgroup: dropping parent refcount after pd_free_fn() is done\n\nSome cgroup policies will access parent pd through child pd even\nafter pd_offline_fn() is done. If pd_free_fn() for parent is called\nbefore child, then UAF can be triggered. Hence it's better to guarantee\nthe order of pd_free_fn().\n\nCurrently refcount of parent blkg is dropped in __blkg_release(), which\nis before pd_free_fn() is called in blkg_free_work_fn() while\nblkg_free_work_fn() is called asynchronously.\n\nThis patch make sure pd_free_fn() called from removing cgroup is ordered\nby delaying dropping parent refcount after calling pd_free_fn() for\nchild.\n\nBTW, pd_free_fn() will also be called from blkcg_deactivate_policy()\nfrom deleting device, and following patches will guarantee the order.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-54107.json)","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":230093,"id":"CVE-2023-54107","ts":1793124789336,"field":"cvss","old":"5.8","new":"7.8"},{"seq":230092,"id":"CVE-2023-54107","ts":1793124789336,"field":"severity","old":"medium","new":"high"},{"seq":223737,"id":"CVE-2023-54107","ts":1792238382153,"field":"cvss","old":"7.8","new":"5.8"},{"seq":223736,"id":"CVE-2023-54107","ts":1792238382153,"field":"severity","old":"high","new":"medium"}]}