CVE-2026-63802

Last refreshed2026-10-17

Status: UPDATED | Advisory ID: CVE-2026-63802

Key Details

CVE	CVE-2026-63802
CVSS Score / Version	7.8 (High) / CVSS v3.1
Updated	2026-10-16
CVSS Vector	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`
CVSS Prose	attack vector is local; attack complexity is low; privileges required is low; user interaction is none; scope is unchanged; confidentiality impact is high; integrity impact is high; availability impact is high.
Affected products	Linux Kernel
Classified as	CWE-416 (Use After Free)

Vendor	Product	Affected Versions	Patch Status
Linux	Linux Kernel

Vendor

Product

Affected Versions

Patch Status

Linux

Linux Kernel

Subsystems	OT Supporting Infrastructure
Sectors	All Sectors

In the Linux kernel, the following vulnerability has been resolved:

blk-cgroup: fix UAF in __blkcg_rstat_flush()

When multiple blkgs in the same blkcg are released concurrently,

a use-after-free can occur. The race happens when one blkg's

__blkcg_rstat_flush() removes another blkg's iostat entries via

llist_del_all(). The second blkg sees an empty list and proceeds

to free itself while the first is still iterating over its entries.

Move the flush from __blkg_release() (RCU callback) to blkg_release()

(before call_rcu). This ensures the RCU grace period waits for any

concurrent flush's rcu_read_lock() section to complete before freeing. (NVD)

Monitor Linux's web page for any future patch releases.

Source	Reference
NVD	https://nvd.nist.gov/vuln/detail/CVE-2026-63802
CVE	https://www.cve.org/CVERecord?id=CVE-2026-63802

Source

Reference

NVD

CVE