CVE-2026-83999

HIGHPre-NVD 7.07.0—
EchelonGraph scoreHIGH confidence

Score 7.0 from GitHub Security Advisory (severity: HIGH) published 2026-09-08. the CNA's CVSS baseline 7.0; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:microsoft, epss, ghsa
Trending — 4 sources updated this week
7.0EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.0Exploit: None knownExposed: 0

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

Improper link resolution before file access ('link following') in Windows Resilient File System (ReFS) Deduplication Service allows an authorized attacker to elevate privileges locally.

CVSS v3
7.0
EG Score
7.0(high)
EG Risk
32(Track)
EG Risk 32/100SSVC: 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
Severity70% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
11%
KEV
Not listed

Published

September 8, 2026

Last Modified

September 18, 2026

Advisory Details (1)

Auto-updated Sep 8, 2026
Patch available. Sources: microsoft.
microsoft Patch Available

Security Update Guide - Microsoft Security Response Center

Security Update Guide - Microsoft Security Response Center. Patch available via Microsoft Security Update

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83999

Vendor Advisories for CVE-2026-83999(2)

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 52× in last 7d / 94× 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. 2026-09-20 20:16 UTCEPSS rescore
  2. 2026-09-20 11:54 UTCVendor advisory
  3. 2026-09-20 11:54 UTCGHSA enrichment
  4. 2026-09-19 22:49 UTCEG score recompute
  5. 2026-09-19 22:49 UTCVendor advisory
  6. 2026-09-19 22:49 UTCGHSA enrichment
  7. 2026-09-19 09:57 UTCVendor advisory
  8. 2026-09-19 09:57 UTCGHSA enrichment
  9. 2026-09-18 21:06 UTCEG score recompute
  10. 2026-09-18 21:06 UTCVendor advisory
  11. 2026-09-18 21:06 UTCGHSA enrichment
  12. 2026-09-18 19:28 UTCEPSS rescore
  13. 2026-09-18 14:12 UTCVendor advisory
  14. 2026-09-18 14:12 UTCGHSA enrichment
  15. 2026-09-18 11:58 UTCVendor advisory
  16. 2026-09-18 11:58 UTCGHSA enrichment
  17. 2026-09-17 23:06 UTCVendor advisory
  18. 2026-09-17 23:06 UTCGHSA enrichment
  19. 2026-09-17 20:11 UTCVendor advisory
  20. 2026-09-17 20:11 UTCGHSA enrichment
  21. 2026-09-17 19:55 UTCEG score recompute
  22. 2026-09-17 19:55 UTCVendor advisory
  23. 2026-09-17 19:55 UTCGHSA enrichment
  24. 2026-09-17 19:32 UTCEPSS rescore
  25. 2026-09-17 11:03 UTCVendor advisory
Show 69 more
  1. 2026-09-17 11:03 UTCGHSA enrichment
  2. 2026-09-16 22:12 UTCEG score recompute
  3. 2026-09-16 22:12 UTCVendor advisory
  4. 2026-09-16 22:12 UTCGHSA enrichment
  5. 2026-09-16 14:09 UTCEPSS rescore
  6. 2026-09-16 11:38 UTCEG score recompute
  7. 2026-09-16 11:38 UTCVendor advisory
  8. 2026-09-16 11:38 UTCGHSA enrichment
  9. 2026-09-16 05:15 UTCEPSS rescore
  10. 2026-09-15 22:47 UTCVendor advisory
  11. 2026-09-15 22:47 UTCGHSA enrichment
  12. 2026-09-15 17:58 UTCVendor advisory
  13. 2026-09-15 17:58 UTCGHSA enrichment
  14. 2026-09-15 11:48 UTCEG score recompute
  15. 2026-09-15 11:48 UTCVendor advisory
  16. 2026-09-15 11:48 UTCGHSA enrichment
  17. 2026-09-15 03:12 UTCEPSS rescore
  18. 2026-09-15 03:12 UTCEPSS rescore
  19. 2026-09-14 22:57 UTCVendor advisory
  20. 2026-09-14 22:57 UTCGHSA enrichment
  21. 2026-09-14 17:49 UTCVendor advisory
  22. 2026-09-14 17:49 UTCGHSA enrichment
  23. 2026-09-14 15:13 UTCVendor advisory
  24. 2026-09-14 15:13 UTCGHSA enrichment
  25. 2026-09-14 02:22 UTCEG score recompute
  26. 2026-09-14 02:22 UTCVendor advisory
  27. 2026-09-14 02:22 UTCGHSA enrichment
  28. 2026-09-13 13:31 UTCVendor advisory
  29. 2026-09-13 13:31 UTCGHSA enrichment
  30. 2026-09-13 00:40 UTCEG score recompute
  31. 2026-09-13 00:40 UTCVendor advisory
  32. 2026-09-13 00:40 UTCGHSA enrichment
  33. 2026-09-12 11:49 UTCVendor advisory
  34. 2026-09-12 11:49 UTCGHSA enrichment
  35. 2026-09-11 22:58 UTCVendor advisory
  36. 2026-09-11 22:58 UTCGHSA enrichment
  37. 2026-09-11 20:06 UTCVendor advisory
  38. 2026-09-11 20:06 UTCGHSA enrichment
  39. 2026-09-11 17:03 UTCEG score recompute
  40. 2026-09-11 17:03 UTCVendor advisory
  41. 2026-09-11 17:03 UTCGHSA enrichment
  42. 2026-09-11 14:53 UTCEPSS rescore
  43. 2026-09-11 14:53 UTCEPSS rescore
  44. 2026-09-11 14:24 UTCEG score recompute
  45. 2026-09-11 14:24 UTCGHSA enrichment
  46. 2026-09-11 13:51 UTCEG score recompute
  47. 2026-09-11 13:51 UTCGHSA enrichment
  48. 2026-09-11 12:34 UTCEG score recompute
  49. 2026-09-11 12:33 UTCGHSA enrichment
  50. 2026-09-10 23:37 UTCGHSA enrichment
  51. 2026-09-10 11:15 UTCEG score recompute
  52. 2026-09-10 11:14 UTCGHSA enrichment
  53. 2026-09-09 22:19 UTCEG score recompute
  54. 2026-09-09 22:18 UTCGHSA enrichment
  55. 2026-09-09 20:12 UTCEG score recompute
  56. 2026-09-09 20:12 UTCVendor advisory
  57. 2026-09-09 20:12 UTCGHSA enrichment
  58. 2026-09-09 20:09 UTCVendor advisory
  59. 2026-09-09 20:08 UTCGHSA enrichment
  60. 2026-09-09 12:42 UTCVendor advisory
  61. 2026-09-09 12:42 UTCGHSA enrichment
  62. 2026-09-08 23:44 UTCEG score recompute
  63. 2026-09-08 23:44 UTCVendor advisory
  64. 2026-09-08 23:43 UTCGHSA enrichment
  65. 2026-09-08 18:57 UTCEG score recompute
  66. 2026-09-08 18:57 UTCGHSA enrichment
  67. 2026-09-08 17:55 UTCEG score recompute
  68. 2026-09-08 17:55 UTCVendor advisory
  69. 2026-09-08 17:25 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-83999?
CVE-2026-83999 is a high vulnerability published on September 8, 2026. Improper link resolution before file access ('link following') in Windows Resilient File System (ReFS) Deduplication Service allows an authorized attacker to elevate privileges locally.
When was CVE-2026-83999 disclosed?
CVE-2026-83999 was first published in the National Vulnerability Database on September 8, 2026, with the most recent update on September 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-83999 actively exploited?
CVE-2026-83999 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 88.5% of all scored CVEs.
What is the CVSS score of CVE-2026-83999?
CVE-2026-83999 has a CVSS v4.0 base score of 7.0 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-83999?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-83999, 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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