CVE-2026-54352

Budibase has arbitrary file read by workspace-builder via PWA-zip symlink upload

Published

2026-06-22

Modified

2026-08-12

EPSS percentile

30%

Aliases

GHSA-w7mq-r738-x278

Sources

github-advisory

Summary

## Summary `POST /api/pwa/process-zip` at `packages/server/src/api/routes/static.ts:24` accepts a builder-uploaded `.zip`, extracts it with `[email protected]` 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`. `[email protected]` 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. `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. Result: 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. ## Affected `Budibase/budibase` server, `@budibase/server` package, ` ` token come from `GET /api/global/self`. 1. Builder uploads a zip containing one symlink entry that targets `/data/.env`, plus an `icons.json` that references the symlink. ```bash mkdir attack && cd attack ln -s /data/.env evil.png printf '{"name":"x","icons":[{"src":"evil.png","sizes":"192x192","type":"image/png"}]}' > icons.json zip -y attack.zip icons.json evil.png curl -s

Affected packages

Remediation: Upgrade to 3.39.9 or later.

References

• https://github.com/advisories/GHSA-w7mq-r738-x278