CVE-2026-66804

HIGHPre-NVD 7.87.8—
EchelonGraph scoreMEDIUM 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 — 4 sources updated 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: 0.3%CVSS: 7.8Exploit: Elevated riskExposed services: Not assessed

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
7.8HIGHmedium confidence
EG Risk
51
EG Risk 51/100CISA SSVC

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%
CISA SSVC: Track at low or medium mission impact; Track* at high (mission-essential systems).
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.3%
EPSS %ILE
20th
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Track* at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

August 11, 2026

Last Modified

September 29, 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(14)

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

Patch Availability(12)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatrhacm2/console-rhel9:17873392482026-08-26redhat
redhatrhacm2/console-rhel9:17876870622026-08-26redhat
redhatrhacm2/console-rhel9:17873351052026-08-26redhat
redhatrhacm2/console-rhel9:17873392492026-08-26redhat
redhatrhacm2/console-rhel9:17873417802026-08-26redhat
redhatmulticluster-engine/console-mce-rhel9:17870793592026-08-25redhat
redhatmulticluster-engine/console-mce-rhel9:17866688562026-08-25redhat
redhatmulticluster-engine/console-mce-rhel9:17872642502026-08-25redhat
redhatmulticluster-engine/console-mce-rhel9:17872590482026-08-25redhat
redhatmulticluster-engine/console-mce-rhel9:17870793642026-08-25redhat
redhatmulticluster-engine/console-mce-rhel9:17869119772026-08-19redhat
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 32× in last 7d / 158× 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 397 total refreshes for this CVE.

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

Publicly available exploits

(3 references)

Working exploit code is in the public domain (3 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 ↗
  • GitHub PoCZeroDayVPN/CVE-2026-66804-CrossDevice-Service-EoP
    First seen Jul 19, 2026

    sadsadsa

    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 on August 11, 2026, with the most recent update on September 29, 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 0.3% probability of exploitation in the next 30 days (20th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-66804?
CVE-2026-66804 has a CVSS base score of 7.8 (the CNA's own assessment, by microsoft; NVD's own analysis pending).
How do I remediate CVE-2026-66804?
A fix for CVE-2026-66804 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-66804 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-66804

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