Vulnerability-Lookup

GHSA-47P6-69VM-VW6V

Vulnerability from github – Published: 2026-05-26 13:30 – Updated: 2026-06-30 17:39

Summary

@koa/router has an Access Control Bypass

Details

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.

Severity

7.3 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

5.5 (Medium)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "@koa/router"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "14.0.0"
            },
            {
              "fixed": "15.0.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-9495"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-284"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-30T17:39:43Z",
    "nvd_published_at": "2026-05-26T07:16:19Z",
    "severity": "MODERATE"
  },
  "details": "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.",
  "id": "GHSA-47p6-69vm-vw6v",
  "modified": "2026-06-30T17:39:43Z",
  "published": "2026-05-26T13:30:54Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-9495"
    },
    {
      "type": "WEB",
      "url": "https://github.com/koajs/router/issues/202"
    },
    {
      "type": "WEB",
      "url": "https://github.com/koajs/router/pull/206"
    },
    {
      "type": "WEB",
      "url": "https://github.com/koajs/router/commit/d53e17f284557b1f417946f9807ee52290c3c759"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/koajs/router"
    },
    {
      "type": "WEB",
      "url": "https://security.snyk.io/vuln/SNYK-JS-KOAROUTER-12215044"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P",
      "type": "CVSS_V4"
    }
  ],
  "summary": "@koa/router has an Access Control Bypass"
}

CVE-2026-9495 (GCVE-0-2026-9495)

Vulnerability from cvelistv5 – Published: 2026-05-26 05:00 – Updated: 2026-05-26 12:41

Summary

Severity

7.3 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-05-26 12:41 UTC

CWE

CWE-284 - Access Control Bypass
CWE-284 - Improper Access Control

Assigner

snyk CNA under the mitre root

CNA scorecard C 60/100 over 16 records in the last 180 days details

References

4 references

URL	Tags
https://security.snyk.io/vuln/SNYK-JS-KOAROUTER-1…
https://github.com/koajs/router/issues/202
https://github.com/koajs/router/pull/206
https://github.com/koajs/router/commit/d53e17f284…

Impacted products

1 product

Vendor	Product	Version
n/a	@koa/router	Affected: 14.0.0 , < 15.0.0 (semver)

Credits

Ryan Mitchell

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-9495",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-26T12:41:11.506721Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-284",
                "description": "CWE-284 Improper Access Control",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-26T12:41:21.925Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/koajs/router/pull/206"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "@koa/router",
          "vendor": "n/a",
          "versions": [
            {
              "lessThan": "15.0.0",
              "status": "affected",
              "version": "14.0.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Ryan Mitchell"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 7.3,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "LOW",
            "exploitCodeMaturity": "PROOF_OF_CONCEPT",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P",
            "version": "3.1"
          },
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 6.9,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "PROOF_OF_CONCEPT",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "LOW"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-284",
              "description": "Access Control Bypass",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-26T05:00:04.704Z",
        "orgId": "bae035ff-b466-4ff4-94d0-fc9efd9e1730",
        "shortName": "snyk"
      },
      "references": [
        {
          "url": "https://security.snyk.io/vuln/SNYK-JS-KOAROUTER-12215044"
        },
        {
          "url": "https://github.com/koajs/router/issues/202"
        },
        {
          "url": "https://github.com/koajs/router/pull/206"
        },
        {
          "url": "https://github.com/koajs/router/commit/d53e17f284557b1f417946f9807ee52290c3c759"
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "bae035ff-b466-4ff4-94d0-fc9efd9e1730",
    "assignerShortName": "snyk",
    "cveId": "CVE-2026-9495",
    "datePublished": "2026-05-26T05:00:04.704Z",
    "dateReserved": "2026-05-25T09:18:41.020Z",
    "dateUpdated": "2026-05-26T12:41:21.925Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

Publication & reservation Sightings KEV catalogs Other timestamps

Loading timeline…

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted