CVE-2026-63952

Last refreshed2026-10-17

Status: UPDATED | Advisory ID: CVE-2026-63952

Key Details

CVE	CVE-2026-63952
CVSS Score / Version	8.4 (High) / CVSS v3.1
Updated	2026-10-16
CVSS Vector	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N`
CVSS Prose	attack vector is local; attack complexity is low; privileges required is low; user interaction is none; scope is changed; confidentiality impact is high; integrity impact is high; availability impact is none.
Affected products	Linux Kernel

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:

memfd: deny writeable mappings when implying SEAL_WRITE

When SEAL_EXEC is added, SEAL_WRITE is implied to make W^X. But the

implied seal is set after the check that makes sure the memfd can not have

any writable mappings. This means one can use SEAL_EXEC to apply

SEAL_WRITE while having writeable mappings.

This breaks the contract that SEAL_WRITE provides and can be used by an

attacker to pass a memfd that appears to be write sealed but can still be

modified arbitrarily.

Fix this by adding the implied seals before the call for

mapping_deny_writable() is done. (NVD)

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

Source	Reference
NVD	https://nvd.nist.gov/vuln/detail/CVE-2026-63952
CVE	https://www.cve.org/CVERecord?id=CVE-2026-63952

Source

Reference

NVD

CVE