CVE-2026-63823

HIGH
MEDIUM Priority: 0.01 BB Relevance: 41/100
Published: 2026-07-19 Modified: 2026-10-22 First seen: 2026-10-29 Status: active

Attack Surface

Low Complexity No Interaction Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Local
AC: Low
PR: Low
UI: None
S: Unchanged
C: High
I: High
A: High

Description

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.]

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
linux linux_kernel 2.6.16 – 5.10.260

Bug Bounty Relevance

41 / 100
✓ Low complexity
✓ No user interaction

CVSS Score

7.8 / 10.0 v3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploitation Probability

0.16%
Raw Score 0.001610
Percentile 5.2%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00161
2026-10-28
0.00161

Intelligence Sources

nvd ref →