Files
picpeak/backend/__tests__/services/restoreServiceS3Ssrf.test.js
T
Paul NothaftandPaul Nothaft ec03089d57 fix(backend): validate the S3 endpoint host before the restore download (#1383)
* fix(backend): validate the S3 endpoint host before the restore download

downloadFileFromS3() built an S3StorageAdapter and called .download()
directly, skipping the isHostAllowed() private-IP/DNS-rebinding guard
that testConnection() applies elsewhere — an admin with backup.restore
could point the configured S3 endpoint at an internal/metadata address
for unauthenticated egress via the server.

* fix(backend): pin the restore S3 download to its validated DNS resolution

isHostAllowed() was check-then-connect: the AWS SDK re-resolves the
endpoint hostname independently when it actually connects, so a DNS
rebinding condition between the preflight check and the real
connection could still reach a private/internal address. Reuses the
same pinnedRequestOptions() primitive webhookDeliveryWorker.js already
uses, wired into the S3Client's requestHandler.

---------

Co-authored-by: Paul Nothaft <[email protected]>
2026-09-11 10:40:50 +02:00

110 lines
3.9 KiB
JavaScript

/**
* Blind SSRF via the restore S3 download path (GHSA-vm2x-c628-3cx5).
*
* downloadFileFromS3() built a bare S3StorageAdapter and called .download()
* directly, never running the DNS-resolving isHostAllowed() guard that
* testConnection() applies elsewhere — so an admin with backup.restore could
* point the request-supplied S3 endpoint at an internal/metadata address for
* unauthenticated egress via the server. `s3Config` here is fully attacker
* controlled (POST /api/admin/restore/validate and /restore/start take it
* straight from the request body — see routes/adminRestore.js), unlike the
* scheduled-backup S3 endpoint, which is vetted at settings-save time.
*/
const path = require('path');
const fs = require('fs');
const os = require('os');
process.env.NODE_ENV = 'test';
process.env.TEST_DATABASE_PATH = path.join(
fs.mkdtempSync(path.join(os.tmpdir(), 'picpeak-restores3ssrf-')), 'db.sqlite',
);
process.env.JWT_SECRET = process.env.JWT_SECRET || 'restores3ssrf-test-secret';
jest.mock('dns', () => {
const actual = jest.requireActual('dns');
return { ...actual, promises: { ...actual.promises, lookup: jest.fn() } };
});
jest.mock('../../src/services/storage/s3Storage', () =>
jest.fn().mockImplementation(() => ({
download: jest.fn().mockResolvedValue(undefined),
}))
);
const dns = require('dns');
const lookup = dns.promises.lookup;
const S3StorageAdapter = require('../../src/services/storage/s3Storage');
const { RestoreService } = require('../../src/services/restoreService');
describe('downloadFileFromS3 SSRF guard (GHSA-vm2x-c628-3cx5)', () => {
let restoreService;
let originalNodeEnv;
beforeEach(() => {
restoreService = new RestoreService();
lookup.mockReset();
S3StorageAdapter.mockClear();
originalNodeEnv = process.env.NODE_ENV;
process.env.NODE_ENV = 'production';
});
afterEach(() => {
process.env.NODE_ENV = originalNodeEnv;
});
it('rejects an endpoint hostname that resolves to a private/internal address before any network call', async () => {
lookup.mockResolvedValue([{ address: '10.0.0.5', family: 4 }]);
await expect(
restoreService.downloadFileFromS3(
's3://backups/manifest.json',
'/tmp/whatever/manifest.json',
{ endpoint: 'evil-rebind.example.com', accessKeyId: 'k', secretAccessKey: 's' }
)
).rejects.toThrow(/private or internal network address/i);
expect(S3StorageAdapter).not.toHaveBeenCalled();
});
it('rejects an endpoint hostname that resolves to the cloud metadata address', async () => {
lookup.mockResolvedValue([{ address: '169.254.169.254', family: 4 }]);
await expect(
restoreService.downloadFileFromS3(
's3://backups/manifest.json',
'/tmp/whatever/manifest.json',
{ endpoint: 'metadata-rebind.example.com', accessKeyId: 'k', secretAccessKey: 's' }
)
).rejects.toThrow(/private or internal network address/i);
expect(S3StorageAdapter).not.toHaveBeenCalled();
});
it('allows a legitimate public S3 endpoint through to download()', async () => {
lookup.mockResolvedValue([{ address: '93.184.216.34', family: 4 }]);
await restoreService.downloadFileFromS3(
's3://backups/manifest.json',
'/tmp/whatever/manifest.json',
{ endpoint: 's3.example-cdn.com', accessKeyId: 'k', secretAccessKey: 's' }
);
expect(S3StorageAdapter).toHaveBeenCalledTimes(1);
});
it('does not require the guard outside production (dev MinIO stays usable), but still downloads', async () => {
process.env.NODE_ENV = 'development';
lookup.mockResolvedValue([{ address: '10.0.0.5', family: 4 }]); // would be rejected in prod
await restoreService.downloadFileFromS3(
's3://backups/manifest.json',
'/tmp/whatever/manifest.json',
{ endpoint: 'localhost:9000', accessKeyId: 'k', secretAccessKey: 's' }
);
expect(lookup).not.toHaveBeenCalled();
expect(S3StorageAdapter).toHaveBeenCalledTimes(1);
});
});