Findings

CVE-2026-34001

A flaw was found in the X.Org X server.

Published Apr 23, 2026 · updated Jul 15, 2026

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.

Code

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No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Apr 23, 2026 · NIST NVD

    Detected

    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 sy

  2. Jul 15, 2026 · NIST NVD

    Updated

    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 sy

Sources

  • CVE.orgVulnerability recordCVE-2026-34001

    Official CVE identifier

    cve.org
  • NIST NVDVulnerability recordCVE-2026-34001

    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 cr

    nvd.nist.gov

References

CVE-2026-34001 · ZeroDay Findings