CVE-2026-40937

HIGHNVD 8.38.3—
EchelonGraph scoreMEDIUM confidence

Score 8.3 from GitHub Security Advisory (severity: HIGH) published 2026-04-22. NVD baseline CVSS 8.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
8.3
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 8.3Exploit: NoneExposed: 0

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

RustFS is a distributed object storage system built in Rust. Prior to 1.0.0-alpha.94, all four notification target admin API endpoints in rustfs/src/admin/handlers/event.rs use a check_permissions helper that validates authentication only (access key + session token), without performing any admin-action authorization via validate_admin_request. Every other admin handler in the codebase correctly calls validate_admin_request with a specific AdminAction. This is the only admin handler file that skips authorization. A non-admin user can overwrite a shared admin-defined notification target by name, causing subsequent bucket events to be delivered to an attacker-controlled endpoint. This enables cross-user event interception and audit evasion. 1.0.0-alpha.94 contains a patch.

CVSS v3
8.3
EG Score
8.3(medium)
EPSS
21.4%
KEV
Not listed

Published

April 22, 2026

Last Modified

April 24, 2026

Advisory Details (2)

Auto-updated May 4, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

Missing admin authorization on notification target endpoints allows unauthenticated configuration of event webhooks · Advisory · rustfs/rustfs · GitHub

https://github.com/rustfs/rustfs/security/advisories/GHSA-pfcq-4gjr-6gjm
generic

Release 1.0.0-alpha.94 · rustfs/rustfs · GitHub

https://github.com/rustfs/rustfs/releases/tag/1.0.0-alpha.94

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
rustrustfs—ghsa

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.

Affected Packages

(1 across 1 ecosystem)
crates.io(1)
PackageVulnerable rangeFixed inDependents
rustfs———

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 8× in last 7d / 35× 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 109 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-40937?
CVE-2026-40937 is a high vulnerability published on April 22, 2026. RustFS is a distributed object storage system built in Rust. Prior to 1.0.0-alpha.94, all four notification target admin API endpoints in rustfs/src/admin/handlers/event.rs use a checkpermissions helper that validates authentication only (access key + session token), without performing any…
When was CVE-2026-40937 disclosed?
CVE-2026-40937 was first published in the National Vulnerability Database on April 22, 2026, with the most recent update on April 24, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-40937 actively exploited?
CVE-2026-40937 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 21.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-40937?
CVE-2026-40937 has a CVSS v3 base score of 8.3 (NVD).
How do I remediate CVE-2026-40937?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-40937, 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.

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