Injection Flaws in Restify with Cockroachdb

Injection flaws occur when untrusted data is sent to an interpreter as part of a command or query. In a Restify service that uses CockroachDB, the most common vector is dynamic SQL built by string concatenation or interpolation before sending it to the database. Because CockroachDB speaks a PostgreSQL-wire compatible protocol, many Node.js PostgreSQL drivers (e.g., pg) behave similarly to standard PostgreSQL drivers, and patterns that are unsafe in Postgres are equally unsafe in CockroachDB.

Consider a typical endpoint that fetches a user by accountId supplied via query parameters:

const accountId = req.query.accountId;
const query = 'SELECT id, email FROM users WHERE account_id = ' + accountId;
const { rows } = await client.query(query);

If accountId is attacker-controlled (for example, ?accountId=1 OR 1=1), the SQL statement becomes malformed in a way that bypasses intended access boundaries, potentially returning all users. CockroachDB will execute the statement as written, so there is no server-side distinction between a developer-intended query and an injected one. Even when using prepared statements, constructing the SQL string with concatenation before preparing (e.g., client.prepare('find', 'SELECT … WHERE id = ' + id)) reintroduces the risk.

Another variant specific to Restify plugins involves misuse of route parameters combined with dynamic table or column names. For example, using user input to decide which column to sort by without allowlisting exposes the same class of injection:

const sortColumn = req.query.sort;
const sql = `SELECT id, email FROM users ORDER BY ${sortColumn}`;
const { rows } = await client.query(sql);

Here, template literal interpolation places raw input directly into the SQL command structure. CockroachDB will parse and execute the resulting SQL, enabling an attacker to manipulate the shape of the result or inject additional statements depending on driver behavior and connection settings.

In some configurations, an attacker may also attempt second-order injection if application code logs or stores unsanitized inputs and later uses them in administrative scripts or reporting jobs that execute on behalf of the application against CockroachDB. Because the Restify app supplies the credentials, injected payloads executed in these contexts can inherit the same database permissions as the service account.

Injection flaws in this combination also intersect with other checks middleBrick runs, such as Input Validation and Property Authorization. For example, missing validation on numeric IDs can allow non-integer payloads that break parsing logic or expose stack traces, while weak authorization checks may allow one user’s accountId to be replaced with another’s, leading to unauthorized data access under the guise of an injection-driven bypass.

Remediation centers on ensuring that SQL structure is never derived from untrusted data and that all data values are passed as parameters, not interpolated. The following patterns assume you are using the pg-compatible client for CockroachDB in a Restify handler.

1) Use parameterized queries with placeholders for values

Instead of concatenating values into the SQL string, use numbered or named placeholders and pass values separately. This ensures the query structure is fixed and values cannot change SQL grammar.

const accountId = req.query.accountId;
const sql = 'SELECT id, email FROM users WHERE account_id = $1';
const { rows } = await client.query(sql, [accountId]);

2) Use prepared statements for repeated queries

Prepared statements separate SQL definition from execution, which is especially useful for endpoints hit frequently:

await client.prepare('find_user_by_account', 'SELECT id, email FROM users WHERE account_id = $1');
const query = client.query('find_user_by_account', [accountId]);

3) Allowlist dynamic identifiers such as table or column names

Never interpolate identifiers directly. Maintain a map of acceptable values and validate against it before constructing the SQL:

const allowedColumns = new Set(['email', 'created_at', 'updated_at']);
const sortColumn = req.query.sort;
if (!allowedColumns.has(sortColumn)) {
  throw new Error('Invalid sort column');
}
const sql = `SELECT id, email FROM users ORDER BY ${sortColumn}`; // safe after allowlist check
const { rows } = await client.query(sql);

4) Validate and constrain input types early in the handler

Ensure numeric IDs are truly numeric and within expected ranges before they reach the database layer:

const accountId = Number(req.query.accountId);
if (!Number.isInteger(accountId) || accountId <= 0) {
  throw new Error('Invalid account ID');
}

5) Apply principle of least privilege to the CockroachDB user used by Restify

Even if injection occurs, minimizing permissions reduces impact. For read-only endpoints, use a role that cannot write or modify schema:

-- Example role setup in CockroachDB (run separately)
CREATE ROLE readonly_role;
GRANT SELECT ON TABLE users TO readonly_role;

By combining these practices—parameterized queries, prepared statements, strict allowlists, input validation, and least-privilege database credentials—you reduce the attack surface presented by the Restify + CockroachDB stack and ensure that user-controlled data never alters the intended structure of SQL commands.