CVE-2026-66797

MEDIUMPre-NVD 5.45.4—
EchelonGraph scoreMEDIUM confidence

Score 5.4 from GitHub Security Advisory published 2026-08-21. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 5.4; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 4 sources updated this week
5.4EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.5%CVSS: 5.4Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Improper access control in CloudStack's annotation functionality allows unauthorized comment creation and disclosure.

The addAnnotation and listAnnotation APIs perform an ownership check when an entity's UUID is specified, but fail to honor its result correctly. This lets any authenticated user write annotations to, and disclose existing annotations/comments on, an entity they don't own by simply supplying its UUID.

This issue affects Apache CloudStack: from 4.15.0.0 through 4.20.3.0 and from 4.21.0.0 through 4.22.1.0.

Users are recommended to upgrade to version 4.20.3.1 or 4.22.1.1 or later, which fixes the issue.

CVSS v3
5.4
EG Score
5.4MEDIUMmedium confidence
EG Risk
24
EG Risk 24/100CISA 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
Severity54% × 45%
Exploitation0% × 40%
Automatability0% × 15%
CISA SSVC: Track at every mission impact level.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.5%
EPSS %ILE
38th
KEV
Not listed

CISA SSVCTrack at every mission impact level.

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

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (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 21, 2026

Last Modified

August 27, 2026

Advisory Details (1)

Auto-updated Aug 21, 2026
Patch available.
generic
https://lists.apache.org/thread/g6cwddtjrwbh1d56wjz4cfp3fzfm4kbc

Vendor Advisories for CVE-2026-66797(7)

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

Patch Availability(6)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatrhacm2/cluster-backup-rhel9-operator:17872590602026-08-26redhat
redhatrhacm2/cluster-backup-rhel9-operator:17872385002026-08-26redhat
redhatrhacm2/cluster-backup-rhel9-operator:17872275762026-08-26redhat
redhatrhacm2/cluster-backup-rhel9-operator:17871831762026-08-26redhat
redhatrhacm2/cluster-backup-rhel9-operator:17876846682026-08-26redhat
redhatrhacm2/cluster-backup-rhel9-operator:17871831782026-08-26redhat

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 24× in last 7d / 97× 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 168 total refreshes for this CVE.

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

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Frequently asked(5)

What is CVE-2026-66797?
CVE-2026-66797 is a medium vulnerability published on August 21, 2026. Improper access control in CloudStack's annotation functionality allows unauthorized comment creation and disclosure. The addAnnotation and listAnnotation APIs perform an ownership check when an entity's UUID is specified, but fail to honor its result correctly. This lets any authenticated user…
When was CVE-2026-66797 disclosed?
CVE-2026-66797 was first published on August 21, 2026, with the most recent update on August 27, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-66797 actively exploited?
CVE-2026-66797 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (38th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-66797?
CVE-2026-66797 has a CVSS v3.1 base score of 5.4 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-66797?
A fix for CVE-2026-66797 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-66797 are linked in the Vendor Advisories panel on this page.

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