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CVE-2026-118659

Full vulnerability record from the local CVENow database.

Description

Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Prior to 21.0.2, the Happy DOM server-renderer package's ServerRendererServer accepts unauthenticated HTTP/2 requests and resolves attacker-controlled :path values against server.targetOrigin in #onIncomingRequest in packages/@happy-dom/server-renderer/src/ServerRendererServer.ts without confirming that the resolved origin remains trusted before calling fetch. A protocol-relative path can change the destination to an arbitrary HTTP or HTTPS endpoint reachable by the server, including local and internal services, and the proxy relays the fetched response headers and body to the requester. This issue is fixed in version 21.0.2.

Severity
HIGH
CVSS score
7.5 (v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
Published
2026-10-28 21:16:55.967000
Last modified
2026-10-29 19:17:18.813000
View original CVE JSON
{
  "id": "CVE-2026-118659",
  "sourceIdentifier": "[email protected]",
  "published": "2026-10-28T21:16:55.967",
  "lastModified": "2026-10-29T19:17:18.813",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Prior to 21.0.2, the Happy DOM server-renderer package's ServerRendererServer accepts unauthenticated HTTP/2 requests and resolves attacker-controlled :path values against server.targetOrigin in #onIncomingRequest in packages/@happy-dom/server-renderer/src/ServerRendererServer.ts without confirming that the resolved origin remains trusted before calling fetch. A protocol-relative path can change the destination to an arbitrary HTTP or HTTPS endpoint reachable by the server, including local and internal services, and the proxy relays the fetched response headers and body to the requester. This issue is fixed in version 21.0.2."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "capricorn86",
          "product": "happy-dom",
          "versions": [
            {
              "version": "< 21.0.2",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-29T18:27:17.941408Z",
          "id": "CVE-2026-118659",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/capricorn86/happy-dom/commit/1f3ffdf634231361de1a2acb629b4fe8ee1bd85d",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/capricorn86/happy-dom/pull/2520",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/capricorn86/happy-dom/releases/tag/v21.0.2",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/capricorn86/happy-dom/security/advisories/GHSA-pmf4-3xr3-xjhg",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/capricorn86/happy-dom/security/advisories/GHSA-pmf4-3xr3-xjhg",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}