The preventive measures for sql injection attacks include: 1. Conduct hierarchical management of users and strictly control user permissions; 2. When writing SQL language, it is forbidden to directly write variables into SQL statements. You must set the corresponding Parameters to pass relevant variables; 3. When specifically checking input or submitted variables, convert or filter characters such as single quotes, double quotes, colons, etc.; 4. Use security parameters; 5. Through professional scanning tools, you can Timely scanning to detect corresponding vulnerabilities in the system; 6. Multi-layer verification; 7. Database information encryption.
The operating environment of this tutorial: Windows 7 system, Dell G3 computer.
SQL injection attack is one of the most dangerous web vulnerabilities. It is extremely harmful and has unimaginable consequences. Therefore, it has received great attention from everyone. So do you know what methods are available to prevent SQL injection attacks? Let’s take a look at the detailed introduction.
SQL injection attacks are very harmful, and it is difficult for firewalls to intercept attacks. The main methods to prevent SQL injection attacks include the following aspects.
1. Hierarchical management
Conduct hierarchical management of users and strictly control user permissions. For ordinary users, it is prohibited to grant relevant permissions such as database creation, deletion, modification, etc. Only system administrators have the authority to add, delete, modify, and check.
2. Parameter value transfer
When programmers write SQL language, they are prohibited from writing variables directly into SQL statements. They must pass relevant parameters by setting corresponding parameters. Variables. Thereby suppressing SQL injection. Data input cannot be embedded directly into the query statement. At the same time, it is necessary to filter the input content and filter out unsafe input data. Or pass input variables by parameter value, which can prevent SQL injection attacks to the greatest extent.
3. Basic filtering and secondary filtering
Before the SQL injection attack, the intruder submits special characters such as and by modifying the parameters to determine whether there is a vulnerability, and then select , update and other characters to write SQL injection statements. Therefore, to prevent SQL injection, user input must be checked to ensure the security of data input. When specifically checking input or submitted variables, single quotes, double quotes, colons and other characters must be converted or filtered to effectively prevent SQL injection.
Of course there are many dangerous characters. When obtaining user input submission parameters, basic filtering must be performed first, and then secondary filtering must be performed based on the function of the program and the possibility of user input to ensure the security of the system.
4. Use security parameters
SQL database in order to effectively suppress the impact of SQL injection attacks. Special SQL security parameters are set when designing the SQLServer database. When writing programs, security parameters should be used as much as possible to prevent injection attacks, thereby ensuring the security of the system.
5. Vulnerability Scanning
In order to prevent SQL injection attacks more effectively, as a system administrator, in addition to setting up effective preventive measures, you should also promptly discover the presence of SQL attack security in the system. loopholes. System administrators can purchase some SQL vulnerability scanning tools. Through professional scanning tools, corresponding vulnerabilities in the system can be scanned in a timely manner.
6. Multi-layer verification
Today’s website system functions are becoming more and more complex. To ensure the security of the system, visitors' data input must undergo strict verification before they can enter the system. Inputs that fail the verification are directly denied access to the database, and an error message is sent to the upper-level system. At the same time, the relevant input information of the visitor is verified in the client access program, thereby more effectively preventing simple SQL injection. But if the lower layer of multi-layer authentication passes the verification data, then an attacker who bypasses the client can access the system at will. Therefore, when performing multi-layer verification, each layer must cooperate with each other. Only by implementing effective verification protection on both the client and system sides can we better prevent SQL injection attacks.
7. Database information encryption
Traditional encryption and decryption methods are roughly divided into three types: symmetric encryption, asymmetric encryption, and irreversible encryption.
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