CVE-2026-66803

CRITICALPre-NVD 10.010.0—
EchelonGraph scoreMEDIUM confidence

Score 10.0 from GitHub Security Advisory (severity: CRITICAL) published 2026-07-30. the CNA's CVSS baseline 10.0; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:microsoft, epss, ghsa
Trending — 4 sources updated this week
10.0EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 10.0Exploit: None knownExposed: 0

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

Improper access control in Azure Cosmos DB allows an unauthorized attacker to execute code over a network.

CVSS v3
10.0
EG Score
10.0(medium)
EG Risk
60(Track)
EG Risk 60/100SSVC: 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
Severity100% × 45%
Exploitation1% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
44%
KEV
Not listed

Published

July 30, 2026

Last Modified

September 9, 2026

Advisory Details (1)

Auto-updated Sep 9, 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-2026-66803

Vendor Advisories for CVE-2026-66803(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 62× in last 7d / 311× 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 563 total refreshes for this CVE.

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-66803?
CVE-2026-66803 is a critical vulnerability published on July 30, 2026. Improper access control in Azure Cosmos DB allows an unauthorized attacker to execute code over a network.
When was CVE-2026-66803 disclosed?
CVE-2026-66803 was first published in the National Vulnerability Database on July 30, 2026, with the most recent update on September 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-66803 actively exploited?
CVE-2026-66803 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 55.6% of all scored CVEs.
What is the CVSS score of CVE-2026-66803?
CVE-2026-66803 has a CVSS v4.0 base score of 10.0 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-66803?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-66803, 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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