CVE-2026-9495

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.

Versions of the package @koa/router from 14.0.0 and before 15.0.0 are vulnerable to Access Control Bypass due to the middleware being silently dropped from the execution chain when the router prefix contains path parameters. Depending on what the skipped middleware was supposed to protect, an attacker could bypass authentication and authorization, evade rate limiting or bypass input sanitization.

CVSS v3
7.3
EG Score
7.3(medium)
EPSS
28.2%
KEV
Not listed

Published

May 26, 2026

Last Modified

May 26, 2026

Advisory Details (3)

Auto-updated Jun 9, 2026
⚠️ Active exploitation confirmed. No patch confirmed yet. Sources: github_pr.
github_pr

Fix: Ensure .use() middleware works when path or prefix contains parameters

Upstream fix in progress (PR #206 · koajs/router, state=closed)

https://github.com/koajs/router/pull/206
generic🔴 Active Exploitation

Access Control Bypass in @koa/router | CVE-2026-9495 | Snyk

https://security.snyk.io/vuln/SNYK-JS-KOAROUTER-12215044
generic

[fix] Router middleware not applied when prefix contains path parameters (v14.0.0 regression) · Issue #202 · koajs/router · GitHub

https://github.com/koajs/router/issues/202

Vendor Advisories for CVE-2026-9495(1)

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

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
@koa/router—15.0.0—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 46× 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 137 total refreshes for this CVE.

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

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-9495?
CVE-2026-9495 is a high vulnerability published on May 26, 2026. Versions of the package @koa/router from 14.0.0 and before 15.0.0 are vulnerable to Access Control Bypass due to the middleware being silently dropped from the execution chain when the router prefix contains path parameters. Depending on what the skipped middleware was supposed to protect, an…
When was CVE-2026-9495 disclosed?
CVE-2026-9495 was first published in the National Vulnerability Database 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-2026-9495 actively exploited?
CVE-2026-9495 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 28.2% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-9495?
CVE-2026-9495 has a CVSS v3 base score of 7.3 (NVD).
How do I remediate CVE-2026-9495?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-9495, 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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