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Automated Security Protocol

How to fix SQL Injection (Legacy & Modern)
in Poem

Executive Summary

SQL Injection in the Rust ecosystem, specifically within the Poem framework, usually stems from a fundamental failure: treating user input as trusted executable code. Whether you are using raw SQL or an abstraction layer like sqlx, the moment you use string interpolation (format!) to build a query, you have lost. Modern AppSec demands parameterized queries or type-safe ORMs to ensure the data plane and control plane remain strictly separated.

The Vulnerable Pattern

VULNERABLE CODE
#[handler]
async fn get_user_vulnerable(Path(user_id): Path, db: Data<&PgPool>) -> String {
    // DANGER: String interpolation creates a massive SQLi vector.
    // An attacker can pass '1; DROP TABLE users;--' as the user_id.
    let query = format!("SELECT username FROM users WHERE id = '{}'", user_id);

let row: (String,) = sqlx::query_as(&query)
    .fetch_one(db.0)
    .await
    .unwrap();

row.0


}

The Secure Implementation

The vulnerable code utilizes Rust's `format!` macro to bake user input directly into the SQL string. This allows an attacker to break out of the string literal and execute arbitrary commands. The secure implementation leverages `sqlx`'s binding mechanism (`$1` and `.bind()`). This tells the database to pre-compile the SQL structure and treat the bound variable strictly as data. Even if the input contains SQL keywords or control characters, they are ignored by the parser, effectively neutralizing the injection vector.

SECURE CODE
#[handler]
async fn get_user_secure(Path(user_id): Path, db: Data<&PgPool>) -> Result> {
    // SECURE: Using parameterized queries (prepared statements).
    // The database driver handles the input as a literal value, not part of the SQL command.
    let user = sqlx::query_as::<_, User>("SELECT id, username FROM users WHERE id = $1")
        .bind(user_id)
        .fetch_one(db.0)
        .await
        .map_err(|e| InternalServerError(e))?;

Ok(Json(user))


}

System Alert • ID: 5750
Target: Poem API
Potential Vulnerability

Your Poem API might be exposed to SQL Injection (Legacy & Modern)

74% of Poem apps fail this check. Hackers use automated scanners to find this specific flaw. Check your codebase before they do.

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