This form of attack is primarily used as an alternative to the in-band and inferential SQLi techniques. The attacker can only carry out this form of attack when certain features are enabled on the database server used by the web application. The attacker can thus work out if the message they used returned true or false, without relying on data from the database. Based on the result, an HTTP response will be generated instantly or after a waiting period. The attacker can see from the time the database takes to respond, whether a query is true or false.
Boolean-that attacker sends a SQL query to the database prompting the application to return a result.Blind SQL injections can be classified as follows: This method is called blind SQLi because the data is not transferred from the website database to the attacker, thus the attacker cannot see information about the attack in-band.īlind SQL injections rely on the response and behavioral patterns of the server so they are typically slower to execute but may be just as harmful.
The attacker sends data payloads to the server and observes the response and behavior of the server to learn more about its structure. This response may contain data that can be leveraged by the attacker. Union-based SQLi-this technique takes advantage of the UNION SQL operator, which fuses multiple select statements generated by the database to get a single HTTP response.The attacker can potentially use the data provided by these error messages to gather information about the structure of the database. Error-based SQLi-the attacker performs actions that cause the database to produce error messages.There are two sub-variations of this method: In-band SQLi’s simplicity and efficiency make it one of the most common types of SQLi attack. The attacker uses the same channel of communication to launch their attacks and to gather their results. You can classify SQL injections types based on the methods they use to access backend data and their damage potential. SQL injections typically fall under three categories: In-band SQLi (Classic), Inferential SQLi (Blind) and Out-of-band SQLi. WHERE ItemNumber = " & Request.QueryString("ItemID")Ī user-provided input can then generates the following SQL query: SELECT ItemName, ItemDescriptionĪs you can gather from the syntax, this query provides the name and description for item number 999. Different SQL elements implement these tasks, e.g., queries using the SELECT statement to retrieve data, based on user-provided parameters.Ī typical eStore’s SQL database query may look like the following: SELECT ItemName, ItemDescriptionįrom this, the web application builds a string query that is sent to the database as a single SQL statement: sql_query= " SQL queries are used to execute commands, such as data retrieval, updates, and record removal. SQL is a standardized language used to access and manipulate databases to build customizable data views for each user. While this vector can be used to attack any SQL database, websites are the most frequent targets. When calculating the potential cost of an SQLi, it’s important to consider the loss of customer trust should personal information such as phone numbers, addresses, and credit card details be stolen.
A successful attack may result in the unauthorized viewing of user lists, the deletion of entire tables and, in certain cases, the attacker gaining administrative rights to a database, all of which are highly detrimental to a business. The impact SQL injection can have on a business is far-reaching. This information may include any number of items, including sensitive company data, user lists or private customer details.
#ACUNETIX BLIND SQL INJECTION TOOL TUTORIAL CODE#
SQL injection, also known as SQLI, is a common attack vector that uses malicious SQL code for backend database manipulation to access information that was not intended to be displayed.