Prevent SQL Injection Attacks

A SQL injection is a common attack technique that involves placing malicious code within improperly formatted SQL queries. This can happen when users are prompted to provide credentials to access the database. However, instead of inputting a username, a hacker deploying a SQL injection attack will enter a SQL statement designed to secretly run or trick the database into thinking it is a command. If successful, a SQL injection allows attackers to access, edit, and potentially even delete a database.

A typical SQL injection attack involves two phases:

• Research: During the research portion, the hacker will enter unexpected values for arguments in the SQL statement, which can inadvertently reveal vulnerabilities in how the field queries the database. The error messages the application gives in response to these unexpected values help the attacker create a SQL command that exploits the identified vulnerability in the database.
• Attack: During the attack phase, the hacker enters an input value the database interprets as a SQL command instead of data. The database runs that command, which can have serious consequences, ranging from information leaks to deletion of the entire database, depending on the severity of the attack.

To prevent SQL injection attacks, you need to be familiar with the different types of SQL injections:

In-band SQL injections: These injections happen when attackers use the same communication channel to launch attacks and gather results. The two types of in-band SQL injections are:

• Error-based SQL injections: Hackers use database error messages to gather information about database structure.
• Union-based SQL injections: These injections retrieve data by appending UNION SELECT statements to existing queries, so attackers can combine results from different queries to access unauthorized data.

Blind SQL injections: Attackers send payloads and observe the web application's response. They then use that information to reconstruct the database structure. The two forms of blind SQL injections are:

• Boolean-based (content-based) blind SQL injections: These SQL injections allow attackers to infer data from an application’s behavior after sending a query.
• Time-based blind SQL injections: This involves sending SQL queries to the database and observing the response time to tell if the query result is TRUE or FALSE.

Out-of-band SQL injections: Bad actors use these injections when they can’t launch their attack and gather information from the same channel or when the server is too slow or unstable. However, these attacks can only happen if the web application’s database server has specific features enabled.

When it comes to preventing SQL injection, it’s also important to understand where attackers are exploiting vulnerabilities. Notably, they can manipulate:

• SELECT statements: Attackers can inject code into SELECT statements to filter or retrieve data and bypass authentication to access sensitive data.
• WHERE clauses: By targeting these clauses, attackers can manipulate conditions to gain access to data.
• ORDER BY clauses: By injecting into the ORDER BY clauses, attackers can manipulate query sorting and create database errors that provide insights into a structure.
• JOIN conditions: SQL injections in JOIN statements can link unrelated tables or reveal relationships between data.
• INSERT and UPDATE statements: Attackers can also inject code into fields used to create or update records, potentially altering data or storing harmful payloads for later execution.

There’s no failsafe SQL injection attack prevention method, but SQL injection prevention best practices make it harder for hackers to gain access. You should:

• Treat all user-submitted data as potentially hazardous.
• Use functions such as mysql_real_escape_string() to remove dangerous characters and validate input before passing it to the SQL query.
• Filter input values such as email addresses and phone numbers to only allow valid characters.
• Use prepared statements, parameterized queries, and stored procedures to reduce malicious input, but don’t rely on them as your only defense.
• Regularly update and patch applications and databases to fix vulnerabilities.
• Use firewalls to help filter malicious data.
• Disable unnecessary database features to reduce potential attack surfaces.
• Limit database account privileges to minimize damage in case of a breach.
• Monitor database logs for suspicious activity that could indicate a SQL injection attack.

SEM supports a wide variety of security assessment protocols and applications, including file integrity monitoring, automated incident response, and intrusion detection to help you maintain a secure database and protect against SQL injection attacks. When hackers access a database via SQL injection, they almost always leave behind a trail of SQL errors, which can serve as an early warning sign that an attack is in progress.

SolarWinds SEM offers real-time log monitoring capabilities and cyber threat intelligence feeds, enabling you to collect and monitor threat data easily, correlate events, and discover data anomalies. As a result, you can identify and respond to threats, including SQL injection attacks, faster. Additionally, SEM has pre-built SQL injection rules and alerts to keep you informed. It can also disable users and processes and perform other automated threat responses to help prevent SQL injection attacks when SQL injection indicators are detected.

SolarWinds Observability Self-Hosted can help you gain additional visibility, allowing you to prevent SQL injection attacks more easily. It can be easily integrated with SEM (Security Observability) and helps keep an eye on your on-premises and cloud-based assets, improving SQL injection protection.

SolarWinds Observability Self-Hosted features a convenient dashboard that makes viewing vulnerabilities and risks simple, allowing you to identify, prioritize, and mitigate risks more easily. The dashboard calculates each node’s risk score based on the CVE scoring, and the total infrastructure score is calculated by aggregating all node scores. You can also use the SolarWinds Observability Self-Hosted dashboard to keep tabs on saved searches, which can help you maintain real-time visibility over vulnerabilities, respond to potential threats quickly, and prevent SQL injection attacks.

Related features:

• SQL Server Audits
• How to Stop a DDoS Attack
• Cross Site Scripting Prevention Tool
• Ransomware Detection Software
• Botnet Detection Tool
• Privileged Account Management Tool
• Event Correlation Software
• Firewall Security Audit Tool
• Firewall Security Management Software
• Network Security Monitoring Software

Related tools:

• SolarWinds Access Rights Manager
• SolarWinds Observability Self-Hosted