CVE-2026-63509

CRITICALNVD 8.89.9▲
EchelonGraph scoreMEDIUM confidence

Score 9.9 from GitHub Security Advisory (severity: CRITICAL) published 2026-08-21. NVD baseline CVSS 8.8; sources differ by 1.1.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 4 sources updated this week
9.9EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 8.8Exploit: None knownExposed: 0

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

Relative path traversal in Microsoft Fabric allows an authorized attacker to elevate privileges over a network.

CVSS v3
8.8
EG Score
9.9(medium)
EG Risk
45(Track)
EG Risk 45/100SSVC: 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
Severity99% × 45%
Exploitation1% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
48%
KEV
Not listed

Published

August 20, 2026

Last Modified

September 16, 2026

Advisory Details (1)

Auto-updated Sep 3, 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-2026-63509

Vendor Advisories for CVE-2026-63509(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.

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 87× in last 7d / 390× 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 390 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-63509?
CVE-2026-63509 is a critical vulnerability published on August 20, 2026. Relative path traversal in Microsoft Fabric allows an authorized attacker to elevate privileges over a network.
When was CVE-2026-63509 disclosed?
CVE-2026-63509 was first published in the National Vulnerability Database on August 20, 2026, with the most recent update on September 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-63509 actively exploited?
CVE-2026-63509 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 51.6% of all scored CVEs.
What is the CVSS score of CVE-2026-63509?
CVE-2026-63509 has a CVSS v3 base score of 8.8 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.9.
How do I remediate CVE-2026-63509?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-63509, 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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