Prevent three attacks on Web application servers

WWW, some people call it the Web, is the application of the current Internet, the fastest growing network information services, but also the most convenient and most popular information service types. Its biggest feature is integration, it can integrate a variety of applications, such as FTP, E-Mail, database, etc., this integration also makes Web services become one of the most vulnerable servers.

Of course, we are more and more concerned about security issues, there are many factors affecting security. such as viruses, spyware, vulnerabilities, and so on. And malware has a long history, far beyond our memory. This trend seems to have shown no signs of slowing, especially as Trojan horses and other malicious code are increasingly rampant today. However, the malware problem pales in comparison to the attackers ' use of vulnerable application servers to steal large amounts of critical information.

Why are Web application servers a target for attackers? The reason is simple because they are publicly accessible and tightly connected to the backend database server, which stores a huge amount of information that makes criminals covet. So how does an attacker use a front-end Web application to hack back-end database server barriers?

SQL injection attacks

SQL injection attacks are now increasingly popular as a way to steal confidential information on the Internet. A SQL injection attack includes one such method: An attacker enters a SQL query into a Web form's search field, and if the query is accepted by the Web application, it is passed to the backend database server to execute it, which, of course, is based on read/ Write access operation is permitted under the premise. This can lead to two scenarios, one in which an attacker can view the contents of a database and an attacker who deletes the contents of a database. Whatever happens, it means disaster to the user.

Many people may think that SQL injection attacks require advanced knowledge. On the contrary, in essence, anyone who has a basic understanding of SQL and has a certain query program (which is ubiquitous on the Internet) can implement this attack.

Blind SQL injection attack

Blind SQL injection attacks are another way to launch an attack, but they are a slightly different approach. When performing a standard SQL injection attack, an attacker inserts an SQL query into a Web application, expecting the server to return an error message. This error message enables an attacker to obtain the information needed to perform a more precise attack. This causes the database administrator to believe that a message that eliminates this error will resolve the potential problem that is causing the SQL injection attack. Administrators may not realize that while this hides error messages, this vulnerability persists. This adds some difficulty to an attacker, but does not prevent an attacker from gathering information using error messages, and an attacker will continue to send bogus SQL queries to the server for access to the database.

Cross-site scripting attacks

Cross-site scripting attacks, also known as XSS or CSS, are a technique that hackers can use to compromise Web applications that provide dynamic Web pages. Many Web sites today provide dynamic pages consisting of information about multiple source sites that are built dynamically by users. If the Web site administrator does not pay attention to this issue, malicious content can be inserted into a Web page to collect confidential information or simply execute on a client-side system.

Confrontation means

There are many countermeasures and measures against Web application server attacks. A sober understanding of the problem is undoubtedly the most important. Many business organizations are focusing on some preventative measures that need to be implemented, but are unaware of how these attacks are carried out. If you do not understand how Web application server attacks work, the countermeasures will not be effective, and simply relying on firewalls and intrusion prevention systems cannot fundamentally solve the problem. For example, if your Web application server does not filter user input, you are vulnerable to these types of attacks.

Another key issue ahead of attackers is the regular overhaul of your Web application. In the technical field, "Mend, Wei" may not be applicable, because if you do not check in time to repair your "wall", you will lose more than "sheep", most likely your entire "pen" or even more.