Cyber Resilience

CVE-2026-50260

High

Published: 05 June 2026

Published
05 June 2026
Modified
11 June 2026
KEV Added
Patch
CVSS Score v3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0019 9.0th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-50260 is a high-severity Use After Free (CWE-416) vulnerability in Redhat Enterprise Linux. Its CVSS base score is 7.8 (High).

Operationally, ranked at the 9.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

A use-after-free flaw was found in the X.Org X server and Xwayland in FreeCounter(). A client that sets up multiple SyncCounters and awaits on those triggers can trigger a use-after-free when destroying those counters via a second client connection. This…

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may be used to crash the server, or for privilege escalation if the X server runs as root.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

x.org
x server
≤ 21.1.23
x.org
xwayland
≤ 24.1.12
redhat
enterprise linux
10.0, 7.0, 8.0, 9.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

References