CVE-2026-64036

Last refreshed2026-10-13

Status: UPDATED | Advisory ID: CVE-2026-64036

Key Details

CVE	CVE-2026-64036
CVSS Score / Version	7.8 (High) / CVSS v3.1
Updated	2026-10-13
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-129 (Improper Validation of Array Index)

Affected Products, Subsystems & Sectors

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

What to Know

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

cgroup/rstat: validate cpu before css_rstat_cpu() access

css_rstat_updated() is exposed as a BPF kfunc and accepts a

caller-provided cpu argument. The function uses cpu for per-cpu rstat

lookups without checking whether it refers to a valid possible CPU.

A BPF iter/cgroup program with CAP_BPF and CAP_PERFMON can pass an

invalid cpu value. On an unfixed UBSCAN_BOUNDS test kernel, cpu ==

0x7fffffff triggers:

UBSAN: array-index-out-of-bounds in kernel/cgroup/rstat.c:31:9

index 2147483647 is out of range for type 'long unsigned int [64]'

Call Trace:

css_rstat_updated

bpf_iter_run_prog

cgroup_iter_seq_show

bpf_seq_read

Add cpu validation to the BPF-facing css_rstat_updated() kfunc and

move the common implementation to __css_rstat_updated() for in-kernel

callers. (NVD)

What to Do

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

References

Source	Reference
NVD	https://nvd.nist.gov/vuln/detail/CVE-2026-64036
CVE	https://www.cve.org/CVERecord?id=CVE-2026-64036

Source

Reference

NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-64036

CVE