CVE-2026-84123

HIGHPre-NVD 8.88.8—
EchelonGraph scoreHIGH confidence

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-09-01. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this week
8.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.8Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Privilege escalation due to use-after-free in the Graphics: WebGPU component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.

CVSS v3
8.8
EG Score
8.8(high)
EG Risk
40(Track)
EG Risk 40/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity88% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
35%
KEV
Not listed

Published

September 1, 2026

Last Modified

September 2, 2026

Advisory Details (3)

Auto-updated Sep 1, 2026
No patch confirmed yet.
generic

Security Vulnerabilities fixed in Firefox ESR 153.2 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-85/
generic

Security Vulnerabilities fixed in Firefox 155 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-82/
generic

Access Denied

https://bugzilla.mozilla.org/show_bug.cgi?id=2060047

Vendor Advisories for CVE-2026-84123(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 25× in last 7d / 92× 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.

  1. 2026-09-25 00:10 UTCEG score recompute
  2. 2026-09-25 00:10 UTCGHSA enrichment
  3. 2026-09-24 14:04 UTCEPSS rescore
  4. 2026-09-24 10:44 UTCGHSA enrichment
  5. 2026-09-23 21:38 UTCEG score recompute
  6. 2026-09-23 21:38 UTCGHSA enrichment
  7. 2026-09-23 17:54 UTCEPSS rescore
  8. 2026-09-23 08:32 UTCGHSA enrichment
  9. 2026-09-22 19:26 UTCEG score recompute
  10. 2026-09-22 19:25 UTCGHSA enrichment
  11. 2026-09-22 16:01 UTCEPSS rescore
  12. 2026-09-22 06:20 UTCEG score recompute
  13. 2026-09-22 06:20 UTCGHSA enrichment
  14. 2026-09-21 21:09 UTCEPSS rescore
  15. 2026-09-21 17:13 UTCGHSA enrichment
  16. 2026-09-21 03:22 UTCEG score recompute
  17. 2026-09-21 03:22 UTCGHSA enrichment
  18. 2026-09-20 20:16 UTCEPSS rescore
  19. 2026-09-20 14:16 UTCGHSA enrichment
  20. 2026-09-20 01:10 UTCEG score recompute
  21. 2026-09-20 01:10 UTCGHSA enrichment
  22. 2026-09-19 12:04 UTCGHSA enrichment
  23. 2026-09-18 22:58 UTCEG score recompute
  24. 2026-09-18 22:58 UTCGHSA enrichment
  25. 2026-09-18 19:28 UTCEPSS rescore
Show 67 more
  1. 2026-09-18 09:52 UTCGHSA enrichment
  2. 2026-09-17 20:46 UTCEG score recompute
  3. 2026-09-17 20:46 UTCGHSA enrichment
  4. 2026-09-17 19:32 UTCEPSS rescore
  5. 2026-09-17 04:44 UTCGHSA enrichment
  6. 2026-09-16 15:38 UTCEG score recompute
  7. 2026-09-16 15:38 UTCGHSA enrichment
  8. 2026-09-16 14:09 UTCEPSS rescore
  9. 2026-09-16 05:15 UTCEPSS rescore
  10. 2026-09-16 02:17 UTCGHSA enrichment
  11. 2026-09-15 13:11 UTCEG score recompute
  12. 2026-09-15 13:11 UTCGHSA enrichment
  13. 2026-09-15 03:12 UTCEPSS rescore
  14. 2026-09-15 03:12 UTCEPSS rescore
  15. 2026-09-15 00:03 UTCGHSA enrichment
  16. 2026-09-14 10:58 UTCGHSA enrichment
  17. 2026-09-13 21:52 UTCEG score recompute
  18. 2026-09-13 21:52 UTCGHSA enrichment
  19. 2026-09-13 08:46 UTCGHSA enrichment
  20. 2026-09-12 19:40 UTCEG score recompute
  21. 2026-09-12 19:40 UTCGHSA enrichment
  22. 2026-09-12 06:34 UTCGHSA enrichment
  23. 2026-09-11 17:27 UTCEG score recompute
  24. 2026-09-11 17:27 UTCGHSA enrichment
  25. 2026-09-11 14:53 UTCEPSS rescore
  26. 2026-09-11 14:53 UTCEPSS rescore
  27. 2026-09-11 03:55 UTCGHSA enrichment
  28. 2026-09-10 14:49 UTCEG score recompute
  29. 2026-09-10 14:49 UTCGHSA enrichment
  30. 2026-09-10 01:43 UTCGHSA enrichment
  31. 2026-09-09 12:33 UTCGHSA enrichment
  32. 2026-09-08 23:27 UTCEG score recompute
  33. 2026-09-08 23:27 UTCGHSA enrichment
  34. 2026-09-08 22:01 UTCEPSS rescore
  35. 2026-09-08 04:02 UTCEG score recompute
  36. 2026-09-08 04:02 UTCGHSA enrichment
  37. 2026-09-07 14:55 UTCGHSA enrichment
  38. 2026-09-07 00:00 UTCEG score recompute
  39. 2026-09-07 00:00 UTCGHSA enrichment
  40. 2026-09-06 13:48 UTCEPSS rescore
  41. 2026-09-06 10:54 UTCGHSA enrichment
  42. 2026-09-05 21:49 UTCEG score recompute
  43. 2026-09-05 21:49 UTCGHSA enrichment
  44. 2026-09-05 15:31 UTCEPSS rescore
  45. 2026-09-05 08:43 UTCGHSA enrichment
  46. 2026-09-04 19:37 UTCEG score recompute
  47. 2026-09-04 19:36 UTCGHSA enrichment
  48. 2026-09-04 06:30 UTCEG score recompute
  49. 2026-09-04 06:30 UTCGHSA enrichment
  50. 2026-09-04 05:07 UTCEPSS rescore
  51. 2026-09-03 17:22 UTCGHSA enrichment
  52. 2026-09-03 04:15 UTCGHSA enrichment
  53. 2026-09-02 15:07 UTCEG score recompute
  54. 2026-09-02 15:07 UTCGHSA enrichment
  55. 2026-09-02 14:12 UTCEPSS rescore
  56. 2026-09-02 04:38 UTCGHSA enrichment
  57. 2026-09-02 04:02 UTCGHSA enrichment
  58. 2026-09-01 22:20 UTCGHSA enrichment
  59. 2026-09-01 21:43 UTCGHSA enrichment
  60. 2026-09-01 21:09 UTCGHSA enrichment
  61. 2026-09-01 15:40 UTCEG score recompute
  62. 2026-09-01 15:40 UTCGHSA enrichment
  63. 2026-09-01 14:27 UTCEG score recompute▲ 8.80
  64. 2026-09-01 14:23 UTCMITRE cvelistV5CVSS v3 → 8.8 · severity → HIGH
  65. 2026-09-01 13:35 UTCNVD update
  66. 2026-09-01 12:45 UTCEG score recompute
  67. 2026-09-01 12:41 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-84123?
CVE-2026-84123 is a high vulnerability published on September 1, 2026. Privilege escalation due to use-after-free in the Graphics: WebGPU component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
When was CVE-2026-84123 disclosed?
CVE-2026-84123 was first published in the National Vulnerability Database on September 1, 2026, with the most recent update on September 2, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-84123 actively exploited?
CVE-2026-84123 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 64.8% of all scored CVEs.
What is the CVSS score of CVE-2026-84123?
CVE-2026-84123 has a CVSS v3.1 base score of 8.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-84123?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-84123, 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

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