PT-2026-46940 · X.Org Foundation+1 · X.Org Server+2

CVE-2026-50260 · Published 2026-04-20 · Updated 2026-07-13

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

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

Name of the Vulnerable Software and Affected Versions X.Org X server (affected versions not specified) Xwayland (affected versions not specified)

Description A use-after-free flaw exists in the FreeCounter() function. This occurs when a client establishes multiple SyncCounters and awaits their triggers, then destroys those counters through a second client connection. This flaw can lead to a server crash or privilege escalation if the X server is running with root privileges.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

LPE

DoS

Use After Free

Weakness Enumeration

CWE-416

Related Identifiers

ALSA-2026:26562

ALSA-2026:26590

ALSA-2026:26610

ALSA-2026:26709

ALSA-2026:28923

ALSA-2026:29844

BDU:2026-08146

CVE-2026-50260

ECHO-ACF9-4716-8B53

OESA-2026-2681

ZDI-26-394

Affected Products

Rocky Linux

X.Org Server

Xwayland

References · 114

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/50xxx/CVE-2026-50260.json · Exploit
• https://osv.dev/vulnerability/ALSA-2026:26590 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-50260 · Vendor Advisory
• https://osv.dev/vulnerability/ALSA-2026:26562 · Vendor Advisory
• https://access.redhat.com/errata/RHSA-2026:36085 · Vendor Advisory
• https://errata.rockylinux.org/RLSA-2026:28923 · Vendor Advisory
• https://bdu.fstec.ru/vul/2026-08146 · Security Note
• https://lists.x.org/archives/xorg-announce/2026-June/003702.html · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-50260 · Vendor Advisory
• https://access.redhat.com/errata/RHSA-2026:26709 · Vendor Advisory
• https://access.redhat.com/errata/RHSA-2026:26590 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-50262 · Security Note
• https://access.redhat.com/errata/RHSA-2026:36633 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-50261 · Security Note
• https://linux.oracle.com/errata/ELSA-2026-26709.html · Vendor Advisory