CVE-2026-34001

HIGHPre-NVD 7.87.8—
EchelonGraph scoreMEDIUM confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-04-23. a secondary CVSS source baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
7.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.8Exploit: NoneExposed: 0

A fix is available — apply it.

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 v3
7.8
EG Score
7.8(medium)
EPSS
17.8%
KEV
Not listed

Published

April 23, 2026

Last Modified

June 30, 2026

Advisory Details (7)

Auto-updated Apr 29, 2026
Patch available. Sources: redhat.
redhat Patch Available

2451109 – (CVE-2026-34001) CVE-2026-34001 xorg: xwayland: X.Org X server: Use-after-free vulnerability leads to server crash and potential memory corruption

Affected: Red Hat Enterprise Linux 9

https://bugzilla.redhat.com/show_bug.cgi?id=2451109
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-34001
redhat Patch Available

Affected: Red Hat Enterprise Linux 8.

https://access.redhat.com/errata/RHSA-2026:11692
redhat Patch Available

Affected: Red Hat Enterprise Linux 9.

https://access.redhat.com/errata/RHSA-2026:11388
redhat Patch Available

Affected: Red Hat Enterprise Linux 9.

https://access.redhat.com/errata/RHSA-2026:11369
redhat Patch Available

Affected: Red Hat Enterprise Linux 10.

https://access.redhat.com/errata/RHSA-2026:11352
redhat Patch Available

Affected: Red Hat Enterprise Linux 9.

https://access.redhat.com/errata/RHSA-2026:10739

Vendor Advisories for CVE-2026-34001(20)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(30)

Vendor / EcosystemFixed in / PatchReleasedSource
redhattigervnc-0:1.12.0-6.el8_6.172026-06-08redhat
redhattigervnc-0:1.1.0-25.el6_10.162026-06-04redhat
redhattigervnc-0:1.11.0-8.el8_4.152026-06-04redhat
redhattigervnc-0:1.12.0-15.el8_8.172026-06-04redhat
redhattigervnc-0:1.8.0-36.el7_9.42026-06-02redhat
redhattigervnc-0:1.14.1-10.el9_62026-06-02redhat
redhattigervnc-0:1.11.0-22.el9_0.172026-05-28redhat
redhatxorg-x11-server-Xwayland-0:21.1.3-2.el8_6.62026-05-28redhat
redhatxorg-x11-server-0:1.20.11-7.el8_62026-05-28redhat
redhatxorg-x11-server-0:1.20.10-4.el8_42026-05-28redhat
redhatxorg-x11-server-0:1.20.11-13.el9_02026-05-28redhat
redhatxorg-x11-server-Xwayland-0:21.1.3-13.el8_82026-05-28redhat
redhatxorg-x11-server-0:1.20.11-18.el8_82026-05-28redhat
redhatxorg-x11-server-0:1.20.11-33.el9_62026-05-26redhat
redhatxorg-x11-server-Xwayland-0:24.1.5-6.el10_02026-05-26redhat
redhatxorg-x11-server-0:1.20.11-28.el9_42026-05-26redhat
redhatxorg-x11-server-Xwayland-0:22.1.9-8.el9_42026-05-26redhat
redhattigervnc-0:1.12.0-14.el9_2.142026-05-26redhat
redhatxorg-x11-server-Xwayland-0:21.1.3-5.el9_02026-05-26redhat
redhatxorg-x11-server-0:1.20.11-20.el9_22026-05-26redhat
redhatxorg-x11-server-Xwayland-0:23.2.7-6.el9_62026-05-26redhat
redhatxorg-x11-server-0:1.20.4-34.el7_92026-05-26redhat
redhatxorg-x11-server-Xwayland-0:21.1.3-10.el9_22026-05-26redhat
redhattigervnc-0:1.13.1-8.el9_4.92026-05-26redhat
redhatxorg-x11-server-Xwayland-0:24.1.9-4.el10_22026-05-19redhat
redhattigervnc-0:1.15.0-7.el9_8.12026-05-19redhat
redhatxorg-x11-server-Xwayland-0:24.1.9-4.el9_82026-05-19redhat
redhatxorg-x11-server-0:1.20.11-34.el9_82026-05-19redhat
redhattigervnc-0:1.15.0-9.el8_102026-05-04redhat
redhatxorg-x11-server-0:1.20.11-28.el8_102026-04-29redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(16)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 8× in last 7d / 70× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 132 total refreshes for this CVE.

  1. 2026-07-06 16:27 UTCEPSS rescore
  2. 2026-07-06 16:27 UTCEPSS rescore
  3. 2026-07-06 02:23 UTCEPSS rescore
  4. 2026-07-06 02:23 UTCEPSS rescore
  5. 2026-07-05 02:30 UTCEPSS rescore
  6. 2026-07-04 06:31 UTCEPSS rescore
  7. 2026-07-01 15:06 UTCEPSS rescore
  8. 2026-06-30 23:22 UTCEPSS rescore
  9. 2026-06-29 14:06 UTCEPSS rescore
  10. 2026-06-29 14:06 UTCEPSS rescore
  11. 2026-06-28 14:07 UTCEPSS rescore
  12. 2026-06-28 14:07 UTCEPSS rescore
  13. 2026-06-28 04:56 UTCEPSS rescore
  14. 2026-06-28 04:56 UTCEPSS rescore
  15. 2026-06-27 03:08 UTCEPSS rescore
  16. 2026-06-25 13:49 UTCEPSS rescore
  17. 2026-06-25 13:49 UTCEPSS rescore
  18. 2026-06-24 14:05 UTCEPSS rescore
  19. 2026-06-23 21:33 UTCEPSS rescore
  20. 2026-06-23 21:33 UTCEPSS rescore
  21. 2026-06-22 14:25 UTCEPSS rescore
  22. 2026-06-22 14:25 UTCEPSS rescore
  23. 2026-06-21 14:56 UTCEPSS rescore
  24. 2026-06-21 14:56 UTCEPSS rescore
  25. 2026-06-21 01:59 UTCEPSS rescore
Show 75 more
  1. 2026-06-19 19:25 UTCEPSS rescore
  2. 2026-06-19 19:25 UTCEPSS rescore
  3. 2026-06-18 17:52 UTCEPSS rescore
  4. 2026-06-18 17:52 UTCEPSS rescore
  5. 2026-06-17 17:53 UTCEPSS rescore
  6. 2026-06-16 17:52 UTCEPSS rescore
  7. 2026-06-15 17:49 UTCEPSS rescore
  8. 2026-06-15 02:27 UTCEG score recompute
  9. 2026-06-15 02:27 UTCVendor advisory
  10. 2026-06-15 02:27 UTCGHSA enrichment
  11. 2026-06-14 23:18 UTCEPSS rescore
  12. 2026-06-14 12:20 UTCEG score recompute
  13. 2026-06-14 12:20 UTCVendor advisory
  14. 2026-06-14 12:20 UTCGHSA enrichment
  15. 2026-06-12 02:18 UTCEG score recompute
  16. 2026-06-12 02:18 UTCVendor advisory
  17. 2026-06-12 02:18 UTCGHSA enrichment
  18. 2026-06-11 14:27 UTCEG score recompute
  19. 2026-06-11 14:27 UTCVendor advisory
  20. 2026-06-11 14:26 UTCGHSA enrichment
  21. 2026-06-11 14:00 UTCEPSS rescore
  22. 2026-06-10 22:18 UTCEPSS rescore
  23. 2026-06-10 15:02 UTCEG score recompute
  24. 2026-06-10 15:02 UTCVendor advisory
  25. 2026-06-10 15:02 UTCGHSA enrichment
  26. 2026-06-10 03:11 UTCEG score recompute
  27. 2026-06-10 03:11 UTCVendor advisory
  28. 2026-06-10 03:11 UTCGHSA enrichment
  29. 2026-06-09 15:19 UTCEG score recompute
  30. 2026-06-09 15:19 UTCVendor advisory
  31. 2026-06-09 15:19 UTCGHSA enrichment
  32. 2026-06-09 03:28 UTCEG score recompute
  33. 2026-06-09 03:28 UTCVendor advisory
  34. 2026-06-09 03:28 UTCGHSA enrichment
  35. 2026-06-08 14:17 UTCEPSS rescore
  36. 2026-06-08 14:17 UTCEPSS rescore
  37. 2026-06-08 05:55 UTCEG score recompute
  38. 2026-06-08 05:55 UTCVendor advisory
  39. 2026-06-08 05:55 UTCGHSA enrichment
  40. 2026-06-07 18:04 UTCEG score recompute
  41. 2026-06-07 18:04 UTCVendor advisory
  42. 2026-06-07 18:04 UTCGHSA enrichment
  43. 2026-06-07 15:25 UTCEPSS rescore
  44. 2026-06-07 15:25 UTCEPSS rescore
  45. 2026-06-07 15:25 UTCEPSS rescore
  46. 2026-06-07 06:12 UTCEG score recompute
  47. 2026-06-07 06:12 UTCVendor advisory
  48. 2026-06-07 06:12 UTCGHSA enrichment
  49. 2026-06-06 18:20 UTCEG score recompute
  50. 2026-06-06 18:20 UTCVendor advisory
  51. 2026-06-06 18:20 UTCGHSA enrichment
  52. 2026-06-06 13:47 UTCEPSS rescore
  53. 2026-06-06 13:47 UTCEPSS rescore
  54. 2026-06-06 04:43 UTCEG score recompute
  55. 2026-06-06 04:43 UTCVendor advisory
  56. 2026-06-06 04:43 UTCGHSA enrichment
  57. 2026-06-05 16:01 UTCEG score recompute
  58. 2026-06-05 16:01 UTCVendor advisory
  59. 2026-06-05 16:01 UTCGHSA enrichment
  60. 2026-06-05 06:10 UTCEPSS rescore
  61. 2026-06-05 06:10 UTCEPSS rescore
  62. 2026-06-05 03:05 UTCEG score recompute
  63. 2026-06-05 03:05 UTCVendor advisory
  64. 2026-06-05 03:05 UTCGHSA enrichment
  65. 2026-06-04 15:13 UTCEG score recompute
  66. 2026-06-04 15:13 UTCVendor advisory
  67. 2026-06-04 15:13 UTCGHSA enrichment
  68. 2026-06-04 03:20 UTCEG score recompute
  69. 2026-06-04 03:20 UTCVendor advisory
  70. 2026-06-04 03:20 UTCGHSA enrichment
  71. 2026-06-03 14:48 UTCEG score recompute
  72. 2026-06-03 14:48 UTCVendor advisory
  73. 2026-06-03 14:48 UTCGHSA enrichment
  74. 2026-06-03 02:56 UTCEG score recompute
  75. 2026-06-03 02:56 UTCVendor advisory

Frequently asked(5)

What is CVE-2026-34001?
CVE-2026-34001 is a high vulnerability published on April 23, 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…
When was CVE-2026-34001 disclosed?
CVE-2026-34001 was first published in the National Vulnerability Database on April 23, 2026, with the most recent update on June 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-34001 actively exploited?
CVE-2026-34001 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 17.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-34001?
CVE-2026-34001 has a CVSS v3 base score of 7.8 (NVD).
How do I remediate CVE-2026-34001?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-34001, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-34001

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