Uncontrolled data in SQL query¶
ID: cpp/sql-injection
Kind: path-problem
Security severity: 8.8
Severity: error
Precision: high
Tags:
- security
- external/cwe/cwe-089
Query suites:
- cpp-code-scanning.qls
- cpp-security-extended.qls
- cpp-security-and-quality.qls
Click to see the query in the CodeQL repository
The code passes user input as part of a SQL query without escaping special elements. It generates a SQL query using sprintf, with the user-supplied data directly passed as an argument to sprintf. This leaves the code vulnerable to attack by SQL Injection.
Recommendation¶
Use a library routine to escape characters in the user-supplied string before converting it to SQL.
Example¶
int main(int argc, char** argv) {
char *userName = argv[2];
// BAD
char query1[1000] = {0};
sprintf(query1, "SELECT UID FROM USERS where name = \"%s\"", userName);
runSql(query1);
// GOOD
char userNameSql[1000] = {0};
encodeSqlString(userNameSql, 1000, userName);
char query2[1000] = {0};
sprintf(query2, "SELECT UID FROM USERS where name = \"%s\"", userNameSql);
runSql(query2);
}
References¶
MSDN Library: SQL Injection.
Common Weakness Enumeration: CWE-89.