Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: use-after-free information disclosure in createsaverwindow()

CVE	CVE-2026-50263
State	PUBLISHED
Assigner	redhat
Source Priority	CVE Program / NVD first with legacy fallback
Published	2026-06-05 12:16:39 UTC
Updated	2026-06-25 14:16:44 UTC
Description	A use-after-free flaw was found in the X.Org X server and Xwayland in CreateSaverWindow(). A client can trigger a use-after-free read after changing window attributes and forcing the screen saver, leading to information disclosure.

Primary CVSS: v3.1 5.5 MEDIUM from [email protected]

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

EPSS: 0.001360000 probability, percentile 0.033600000 (date 2026-06-25)

Problem Types: CWE-416 | CWE-416 Use After Free

Version	Source	Type	Score	Severity	Vector
3.1	[email protected]	Secondary	5.5	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N`
3.1	CNA	CVSS	5.5	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N`

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Type	Vendor	Product	Version	Update	Edition	Language
Operating System	Redhat	Enterprise Linux	10.0	All	All	All
Operating System	Redhat	Enterprise Linux	7.0	All	All	All
Operating System	Redhat	Enterprise Linux	8.0	All	All	All
Operating System	Redhat	Enterprise Linux	9.0	All	All	All
Application	X.org	Xwayland	All	All	All	All
Application	X.org	X Server	All	All	All	All

Source	Vendor	Product	Version	Platforms
CNA	Red Hat	Red Hat Enterprise Linux 10	unaffected 0:24.1.9-4.el10_2.2 * rpm	Not specified
CNA	Red Hat	Red Hat Enterprise Linux 8	unaffected 0:21.1.3-20.el8_10.2 * rpm	Not specified
CNA	Red Hat	Red Hat Enterprise Linux 8	unaffected 0:1.20.11-28.el8_10.2 * rpm	Not specified
CNA	Red Hat	Red Hat Enterprise Linux 8	unaffected 0:1.15.0-10.el8_10 * rpm	Not specified
CNA	Red Hat	Red Hat Enterprise Linux 9	unaffected 0:24.1.9-4.el9_8.2 * rpm	Not specified
CNA	Red Hat	Red Hat Enterprise Linux 9	unaffected 0:1.20.11-34.el9_8.2 * rpm	Not specified
CNA	Red Hat	Red Hat Enterprise Linux 9	unaffected 0:1.15.0-7.el9_8.2 * rpm	Not specified
CNA	Red Hat	Red Hat Enterprise Linux 6	Not specified	Not specified
CNA	Red Hat	Red Hat Enterprise Linux 6	Not specified	Not specified
CNA	Red Hat	Red Hat Enterprise Linux 7	Not specified	Not specified
CNA	Red Hat	Red Hat Enterprise Linux 7	Not specified	Not specified

Reference	Source	Link	Tags
access.redhat.com/security/cve/CVE-2026-50263	[email protected]	access.redhat.com	Third Party Advisory
lists.x.org/archives/xorg-announce/2026-June/003702.html	[email protected]	lists.x.org	Mailing List, Vendor Advisory
access.redhat.com/errata/RHSA-2026:26590	[email protected]	access.redhat.com
access.redhat.com/errata/RHSA-2026:26566	[email protected]	access.redhat.com
access.redhat.com/errata/RHSA-2026:26709	[email protected]	access.redhat.com
access.redhat.com/errata/RHSA-2026:29844	[email protected]	access.redhat.com
gitlab.freedesktop.org/xorg/xserver/-/commit/ecc634f1b2f7aa473d3a267eada98c4918bf9e05	[email protected]	gitlab.freedesktop.org	Patch
redhat.atlassian.net/browse/PSIRTSUPT-16950	[email protected]	redhat.atlassian.net	Permissions Required
bugzilla.redhat.com/show_bug.cgi	[email protected]	bugzilla.redhat.com	Issue Tracking, Third Party Advisory
access.redhat.com/errata/RHSA-2026:26610	[email protected]	access.redhat.com
access.redhat.com/errata/RHSA-2026:28923	[email protected]	access.redhat.com
access.redhat.com/errata/RHSA-2026:26562	[email protected]	access.redhat.com
CVE Program record	CVE.ORG	www.cve.org	canonical
NVD vulnerability detail	NVD	nvd.nist.gov	canonical, analysis

CNA: Upstream acknowledges Anonymous (Trend Micro Zero Day Initiative) as the original reporter. (en)

Source	Time	Event
CNA	2026-05-15T03:14:46.000Z	Reported to Red Hat.
CNA	2026-06-02T00:00:00.000Z	Made public.

There are currently no legacy QID mappings associated with this CVE.