SQL Injection Detection

When to Use

Audit database-backed applications, ORM wrappers, query builders, and any code that constructs SQL queries from user input.

Process

Step 1: Find SQL Query Construction

# JavaScript
grep -rn "query(\|execute(\|\.raw(\|\.rawQuery(" .
grep -rn "knex\.raw\|sequelize\.query\|prisma\.\$queryRaw" .

# Python
grep -rn "cursor\.execute\|execute(\|executemany(" .
grep -rn "\.raw(\|RawSQL\|text(" .
grep -rn "f\".*SELECT\|f\".*INSERT\|f\".*UPDATE\|f\".*DELETE" .

# Go
grep -rn "db\.Query\|db\.Exec\|db\.QueryRow\|tx\.Query" .
grep -rn "fmt\.Sprintf.*SELECT\|fmt\.Sprintf.*INSERT" .

# Ruby
grep -rn "find_by_sql\|execute\|select_all\|where.*#\{" .

# PHP
grep -rn "query(\|prepare(\|exec(\|mysql_query\|mysqli_query" .

Step 2: Check for String Concatenation/Interpolation

# Template literals in SQL
grep -rn "query.*\`.*\$\{" . --include="*.js" --include="*.ts"

# String concatenation in SQL
grep -rn "SELECT.*\+\|INSERT.*\+\|UPDATE.*\+\|DELETE.*\+" .

# Python f-strings in SQL
grep -rn 'f".*SELECT\|f".*INSERT\|f".*UPDATE\|f".*DELETE' .

# Format strings in SQL
grep -rn "\.format(.*SELECT\|\.format(.*INSERT" .

Step 3: Check for Parameterized Queries

Parameterized queries are SAFE:

// SAFE: parameterized
db.query('SELECT * FROM users WHERE id = ?', [userId]);

// UNSAFE: string concatenation
db.query('SELECT * FROM users WHERE id = ' + userId);

Step 4: Check ORM Raw Methods

ORMs are generally safe, but .raw() / .query() methods often bypass protections:

// SAFE: ORM query builder
User.findOne({ where: { id: userId } });

// UNSAFE: raw query with interpolation
sequelize.query(`SELECT * FROM users WHERE id = ${userId}`);

Step 5: Check Non-Parameterizable Locations

Some SQL elements CANNOT be parameterized:

• ORDER BY column names
• Table names
• Column names in SELECT
• LIMIT/OFFSET (in some databases)

If user input reaches these, it is SQLi even with prepared statements.

CVSS Guidance

• Data exfiltration (UNION/blind): HIGH 8.1-8.8
• Data modification: HIGH 8.1
• Unauthenticated with admin data access: CRITICAL 9.8
• Authenticated: HIGH 8.8
• ORDER BY injection (limited): MEDIUM 5.3

References

• Sinks -- SQL query sinks by language
• False Positive Indicators
• PoC Skeleton