CVE-2026-9366

HIGHNVD 7.37.3
EchelonGraph scoreMEDIUM confidence

Score 7.3 from GitHub Security Advisory published 2026-05-26. NVD baseline CVSS 7.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Elevated
7.3
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.3Exploit: NoneExposed: 0

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

A vulnerability was found in NousResearch hermes-agent 2026.4.23. The impacted element is the function _scan_context_content of the file agent/prompt_builder.py. The manipulation results in injection. The attack may be performed from remote. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.

CVSS v3
7.3
EG Score
7.3(medium)
EG Risk
64(Attend)
EG Risk 64/100SSVC: Attend

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
Severity73% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS
22.7%
KEV
Not listed

Published

May 24, 2026

Last Modified

May 26, 2026

Advisory Details (1)

Auto-updated Jun 11, 2026
No patch confirmed yet.
generic

Hermes Agent Context-File Scanner Regex Bypass — Zero-Click Prompt Injection via AGENTS.md / .cursorrules / CLAUDE.md / .hermes.md · GitHub

https://gist.github.com/YLChen-007/581fd92de5548fbaacb2092e848a75cc

Vendor Advisories for CVE-2026-9366(1)

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

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 40× 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 103 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-9366?
CVE-2026-9366 is a high vulnerability published on May 24, 2026. A vulnerability was found in NousResearch hermes-agent 2026.4.23. The impacted element is the function scancontextcontent of the file agent/promptbuilder.py. The manipulation results in injection. The attack may be performed from remote. The exploit has been made public and could be used. The…
When was CVE-2026-9366 disclosed?
CVE-2026-9366 was first published in the National Vulnerability Database on May 24, 2026, with the most recent update on May 26, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-9366 actively exploited?
CVE-2026-9366 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 22.7% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-9366?
CVE-2026-9366 has a CVSS v3 base score of 7.3 (NVD).
How do I remediate CVE-2026-9366?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-9366, 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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