監査で手に入るもの

影響

Full read of the orders table, including customer names, addresses and payment references, and a plausible path to writing or dropping data.

攻撃シナリオ

A request to `/orders/1 or 1=1` returns every order in the table. `/orders/1; drop table orders --` runs a second statement on a driver that allows it. No account is needed: the route is reachable before the session check on line 39.

修正

Pass the identifier as a bound parameter and reject anything that is not a UUID before the query runs.

修正手順

1. Validate the parameter: `if (!isUuid(req.params.id)) return res.status(400).json({ error: "Invalid order id." });`
2. Replace the concatenated query with a parameterized one, as in the patch below.
3. Search the rest of `src/routes` for the same pattern — `db.query("… " +` — and convert those too.
4. Add a regression test that requests `/orders/1 or 1=1` and expects 400.

修正コード

const { rows } = await db.query(
  "select * from orders where id = $1",
  [req.params.id],
);

確認方法

Replay `GET /orders/1%20or%201=1`: it must answer 400, and the Postgres log must show the parameterized statement with the raw value bound, not interpolated.

参考情報

• https://cwe.mitre.org/data/definitions/89.html
• https://owasp.org/Top10/A03_2021-Injection/

影響

Cross-customer data exposure: addresses, totals and payment references belonging to other accounts.

攻撃シナリオ

A customer who signs up legitimately can iterate order identifiers and read other customers' orders. Nothing in the logs distinguishes this from normal use.

修正

Scope the query to the session's user, so an identifier alone is never enough.

修正手順

1. Add `and user_id = $2` to the query and pass `req.session.userId`.
2. Return 404 rather than 403 when the row is missing, so the endpoint does not confirm which identifiers exist.
3. Apply the same scoping to `PATCH /orders/:id` and `POST /orders/:id/refund`.

修正コード

const { rows } = await db.query(
  "select * from orders where id = $1 and user_id = $2",
  [req.params.id, req.session.userId],
);
if (rows.length === 0) return res.status(404).end();

確認方法

Sign in as one account and request an order created by another: the response must be 404, and the row must not appear in the body.

参考情報

• https://cwe.mitre.org/data/definitions/639.html

影響

Full API access to the payment account, independent of this service.

攻撃シナリオ

The key is in every clone and in the commit history. It allows charges, refunds and customer reads against the live account until it is rotated.

修正

Rotate the key first, then remove the fallback so a missing variable fails loudly at boot.

修正手順

1. Roll the key in the Stripe dashboard now; the committed one must be treated as public.
2. Replace the fallback with a hard failure, as in the patch.
3. Purge the value from history (`git filter-repo`) or accept that the old key stays exposed and rely on the rotation.
4. Add a secret scan to CI so the next one is caught before it merges.

修正コード

const key = process.env.STRIPE_SECRET_KEY;
if (!key) throw new Error("STRIPE_SECRET_KEY is not set");
export const STRIPE_KEY = key;

確認方法

Start the service without `STRIPE_SECRET_KEY`: it must refuse to boot instead of using a built-in value.

参考情報

• https://cwe.mitre.org/data/definitions/798.html

影響

Double refunds and a bill at the payment provider for traffic nobody asked for.

攻撃シナリオ

A customer sending the same refund twice within a few milliseconds can have the order refunded twice before the status is written back.

修正

Limit the endpoint per account and make the refund idempotent at the database level.

修正手順

1. Add a limiter keyed on the session's user, e.g. 5 refunds per hour.
2. Claim the refund with a conditional update — `update orders set status = 'refunding' where id = $1 and status = 'paid' returning id` — and only call Stripe when a row comes back.
3. Pass an idempotency key to the Stripe call so a retry cannot charge twice.

確認方法

Fire two refund requests for the same order in parallel: exactly one must reach Stripe, and the second must answer 409.

参考情報

• https://cwe.mitre.org/data/definitions/770.html