FKIE_CVE-2026-50257

Vulnerability from fkie_nvd - Published: 2026-06-05 12:16 - Updated: 2026-06-08 16:45
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
A use-after-free flaw was found in the X.Org X server and Xwayland in miSyncDestroyFence(). A client that sets up multiple fence triggers can trigger a use-after-free function pointer call. An attacker would connect to the X server to set up a fence and await that fence, then a second X connection destroys the fence, causing the use-after-free. This may be used to crash the server, or for privilege escalation if the X server runs as root.
References
secalert@redhat.comhttps://access.redhat.com/security/cve/CVE-2026-50257Third Party Advisory
secalert@redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2485382Issue Tracking, Third Party Advisory
secalert@redhat.comhttps://gitlab.freedesktop.org/xorg/xserver/-/commit/f5abfb61994471023d8c6470428c8e30c411cc0bPatch
secalert@redhat.comhttps://lists.x.org/archives/xorg-announce/2026-June/003702.htmlMailing List, Third Party Advisory
secalert@redhat.comhttps://redhat.atlassian.net/browse/PSIRTSUPT-16950Permissions Required
Impacted products
Vendor Product Version
x.org x_server *
x.org xwayland *
redhat enterprise_linux 7.0
redhat enterprise_linux 8.0
redhat enterprise_linux 9.0
redhat enterprise_linux 10.0
To clipboard 

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  "lastModified": "2026-06-08T16:45:56.703",
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