CVE-2026-63823

Last refreshed2026-10-17

Status: UPDATED | Advisory ID: CVE-2026-63823

Key Details

CVE	CVE-2026-63823
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

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:

keys: Pin request_key_auth payload in instantiate paths

A: request_key() B: KEYCTL_INSTANTIATE_IOV

================ =========================

create auth key

store rka in auth key

wait for helper

get auth key

load rka from auth key

copy user payload

sleep on #PF

helper completed

detach and free rka

destroy auth key

wake up

use rka->target_key

**USE-AFTER-FREE**

Give request_key_auth payloads a refcount. Take a payload reference while

authkey->sem stabilizes the payload and revocation state. Hold that

reference across the instantiate and reject paths. Drop the auth key

owning reference from revoke and destroy.

[jarkko: Replaced the first two paragraphs of text with an actual

concurrency scenario.] (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-2026-63823
CVE	https://www.cve.org/CVERecord?id=CVE-2026-63823

Source

Reference

NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-63823

CVE

https://www.cve.org/CVERecord?id=CVE-2026-63823