---
cve: "CVE-2026-50261"
severity: "HIGH"
cvss: 7.8
epss: "15%"
vendor: "Red Hat"
kev: false
exploited: false
published: "2026-06-05 12:16:39"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-14T01:29:31+02:00"
---

# CVE-2026-50261

> 7.8 HIGH

## Beschreibung

A use-after-free flaw was found in the X.Org X server and Xwayland in SyncChangeCounter(). A client that sets up multiple SyncCounters can trigger a use-after-free when destroying those counters via a second client connection while changing those counters. This may be used to crash the server, or for privilege escalation if the X server runs as root.

## CVSS-Vektor

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

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Gering | bad |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Hoch | bad |

## Patch verfügbar (OSV)

- 8570e9fcec845f68f0c90caa51fd7a24764ea220 (Commit)
- af4b3d7250366e1a3822919e41fcf66da4966af2 (Commit)

## Referenzen

- <https://access.redhat.com/errata/RHSA-2026:26562>
- <https://access.redhat.com/errata/RHSA-2026:26566>
- <https://access.redhat.com/errata/RHSA-2026:26590>
- <https://access.redhat.com/errata/RHSA-2026:26610>
- <https://access.redhat.com/errata/RHSA-2026:26709>
- <https://access.redhat.com/errata/RHSA-2026:28923>
- <https://access.redhat.com/errata/RHSA-2026:29844>
- <https://access.redhat.com/errata/RHSA-2026:36083>
- <https://access.redhat.com/errata/RHSA-2026:36085>
- <https://access.redhat.com/errata/RHSA-2026:36086>
- <https://access.redhat.com/errata/RHSA-2026:36087>
- <https://access.redhat.com/errata/RHSA-2026:36632>
- <https://access.redhat.com/errata/RHSA-2026:36633>
- <https://access.redhat.com/errata/RHSA-2026:36634>
- <https://access.redhat.com/errata/RHSA-2026:36768>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-50261) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_