CVE-2026-66804

HIGHPre-NVD 7.87.8—
EchelonGraph scoreHIGH confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-08-11. the CNA's CVSS baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:microsoft, epss, ghsa
Trending — Patch released this weekElevated
7.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 3%CVSS: 7.8Exploit: Elevated riskExposed: 0

A fix is available — apply it.

Improper access control in Windows Cross Device Service allows an authorized attacker to elevate privileges locally.

CVSS v3
7.8
EG Score
7.8(high)
EG Risk
51(Track)
EG Risk 51/100SSVC: 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
Severity78% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
3%
EPSS %ILE
88%
KEV
Not listed

Published

August 11, 2026

Last Modified

August 20, 2026

Advisory Details (1)

Auto-updated Aug 11, 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-2026-66804

Vendor Advisories for CVE-2026-66804(4)

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

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatrhacm2/console-rhel9:17869083612026-08-19redhat

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.

Data Freshness Timeline

(refreshed 86× in last 7d / 133× 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 133 total refreshes for this CVE.

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

Publicly available exploits

(2 references)

Working exploit code is in the public domain (2 GitHub PoCs). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCRat5ak/CVE-2026-66804-CrossDevice-Service-EoP
    First seen Aug 13, 2026

    CVE-2026-66804 Windows Cross Device virtual camera EoP

    Open source ↗
  • GitHub PoCDavidCarliez/CVE-2026-66804-CrossDevice-LPE
    First seen Jul 23, 2026
    Open source ↗

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-66804?
CVE-2026-66804 is a high vulnerability published on August 11, 2026. Improper access control in Windows Cross Device Service allows an authorized attacker to elevate privileges locally.
When was CVE-2026-66804 disclosed?
CVE-2026-66804 was first published in the National Vulnerability Database on August 11, 2026, with the most recent update on August 20, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-66804 actively exploited?
CVE-2026-66804 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 3% probability of exploitation in the next 30 days, which ranks it in the top 12.0% of all scored CVEs.
What is the CVSS score of CVE-2026-66804?
CVE-2026-66804 has a CVSS v4.0 base score of 7.8 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-66804?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-66804, 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-2026-66804

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