A flaw was found in the X.Org X server. This use-after-free vulnerability occurs in the XSYNC fence triggering logic, specifically within the miSyncTriggerFence() function. An attacker with access to the X11 server can exploit this without user interaction, leading to a server crash and potentially enabling memory corruption. This could result in a denial of service or further compromise of the system.
CVSS Details
- CVSS 3.1 Base Score: 7.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | — | Upgrade xorg-x11-server-XvfbUpgrade tigervnc-licenseUpgrade xorg-x11-server-Xwayland-develUpgrade tigervnc-server-minimalUpgrade xorg-x11-server-XwaylandUpgrade tigervnc-iconsUpgrade tigervnc-selinuxUpgrade xorg-x11-server-XorgUpgrade xorg-x11-server-sourceUpgrade xorg-x11-server-XephyrUpgrade tigervnc-server-moduleUpgrade tigervnc-serverUpgrade xorg-x11-server-commonUpgrade xorg-x11-server-XnestUpgrade xorg-x11-server-develUpgrade tigervncUpgrade xorg-x11-server-Xdmx | Apr 29, 2026 | Apr 27, 2026 |
| Alpine Linux | — | Upgrade xwaylandUpgrade xorg-server | Apr 24, 2026 | Apr 23, 2026 |
| Amazon Linux Ami 2 | — | Upgrade xorg-x11-server-XorgUpgrade tigervnc-serverUpgrade tigervnc-iconsUpgrade xorg-x11-server-commonUpgrade xorg-x11-server-XnestUpgrade xorg-x11-server-XwaylandUpgrade xorg-x11-server-develUpgrade tigervnc-server-appletUpgrade tigervnc-server-moduleUpgrade xorg-x11-server-sourceUpgrade tigervnc-licenseUpgrade tigervnc-server-minimalUpgrade tigervncUpgrade xorg-x11-server-debuginfoUpgrade xorg-x11-server-XvfbUpgrade xorg-x11-server-XephyrUpgrade xorg-x11-server-XdmxUpgrade tigervnc-debuginfo | May 20, 2026 | May 20, 2026 |
| Amazon_linux_2023 | — | Upgrade tigervnc-server-debuginfoUpgrade tigervnc-selinuxUpgrade xorg-x11-server-debuginfoUpgrade tigervncUpgrade xorg-x11-server-Xnest-debuginfoUpgrade xorg-x11-server-Xwayland-debugsourceUpgrade xorg-x11-server-Xwayland-develUpgrade xorg-x11-server-Xvfb-debuginfoUpgrade tigervnc-serverUpgrade xorg-x11-server-XwaylandUpgrade xorg-x11-server-XnestUpgrade xorg-x11-server-Xorg-debuginfoUpgrade xorg-x11-server-XvfbUpgrade xorg-x11-server-commonUpgrade tigervnc-server-minimalUpgrade tigervnc-server-moduleUpgrade tigervnc-debuginfoUpgrade xorg-x11-server-XorgUpgrade tigervnc-server-module-debuginfoUpgrade tigervnc-server-minimal-debuginfoUpgrade tigervnc-debugsourceUpgrade xorg-x11-server-sourceUpgrade xorg-x11-server-debugsourceUpgrade tigervnc-licenseUpgrade tigervnc-iconsUpgrade xorg-x11-server-develUpgrade xorg-x11-server-Xwayland-debuginfoUpgrade xorg-x11-server-XephyrUpgrade xorg-x11-server-Xephyr-debuginfo | May 4, 2026 | Apr 23, 2026 |
| Debian | — | Upgrade xorg-server | May 17, 2026 | May 17, 2026 |
| Freebsd | — | Upgrade xorg-serverUpgrade xwayland | Apr 16, 2026 | Apr 14, 2026 |
| Gentoo Linux | — | Upgrade x11-base/xorg-server.Upgrade x11-base/xwayland. | Aug 17, 2026 | Aug 17, 2026 |
| Oracle_linux | — | Upgrade xorg-x11-server-XephyrUpgrade xorg-x11-server-sourceUpgrade xorg-x11-server-XvfbUpgrade xorg-x11-server-develUpgrade xorg-x11-server-commonUpgrade xorg-x11-server-XdmxUpgrade xorg-x11-server-XwaylandUpgrade xorg-x11-server-Xwayland-develUpgrade xorg-x11-server-XnestUpgrade xorg-x11-server-Xorg | Apr 29, 2026 | Apr 23, 2026 |
| Redhat_linux | — | Upgrade xorg-x11-server-Xephyr-debuginfoUpgrade xorg-x11-server-XwaylandUpgrade xorg-x11-server-Xwayland-debugsourceUpgrade tigervncUpgrade tigervnc-serverUpgrade xorg-x11-server-XorgUpgrade xorg-x11-server-debugsourceUpgrade xorg-x11-server-Xvfb-debuginfoUpgrade xorg-x11-server-Xwayland-debuginfoUpgrade xorg-x11-server-Xdmx-debuginfoUpgrade xorg-x11-server-XnestUpgrade xorg-x11-server-Xwayland-develUpgrade tigervnc-iconsUpgrade xorg-x11-server-Xorg-debuginfoUpgrade xorg-x11-server-develNo solution existsUpgrade tigervnc-debuginfoUpgrade xorg-x11-server-XdmxUpgrade tigervnc-server-moduleUpgrade tigervnc-server-minimal-debuginfoUpgrade xorg-x11-server-XephyrUpgrade tigervnc-selinuxUpgrade xorg-x11-server-XvfbUpgrade tigervnc-server-appletUpgrade tigervnc-licenseUpgrade xorg-x11-server-Xnest-debuginfoUpgrade xorg-x11-server-sourceUpgrade tigervnc-debugsourceUpgrade tigervnc-server-minimalUpgrade tigervnc-server-debuginfoUpgrade xorg-x11-server-commonUpgrade tigervnc-server-module-debuginfoUpgrade xorg-x11-server-debuginfo | Apr 29, 2026 | Apr 23, 2026 |
| Rocky_linux | — | Upgrade xorg-x11-server-XorgUpgrade tigervnc-server-minimalUpgrade xorg-x11-server-XwaylandUpgrade xorg-x11-server-debuginfoUpgrade xorg-x11-server-Xwayland-debuginfoUpgrade xorg-x11-server-Xwayland-develUpgrade tigervnc-serverUpgrade tigervnc-server-minimal-debuginfoUpgrade tigervnc-debugsourceUpgrade xorg-x11-server-Xnest-debuginfoUpgrade xorg-x11-server-debugsourceUpgrade tigervnc-server-module-debuginfoUpgrade tigervnc-server-moduleUpgrade xorg-x11-server-Xorg-debuginfoUpgrade xorg-x11-server-Xdmx-debuginfoUpgrade xorg-x11-server-Xephyr-debuginfoUpgrade xorg-x11-server-XdmxUpgrade xorg-x11-server-commonUpgrade xorg-x11-server-XnestUpgrade xorg-x11-server-XvfbUpgrade xorg-x11-server-Xvfb-debuginfoUpgrade tigervnc-server-debuginfoUpgrade tigervnc-debuginfoUpgrade xorg-x11-server-develUpgrade xorg-x11-server-Xwayland-debugsourceUpgrade xorg-x11-server-XephyrUpgrade tigervnc | Apr 29, 2026 | Apr 28, 2026 |
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