3 Major Gaps in Web Application Security

As technology advances, so do the number of hackers and their capabilities, so it becomes more and more difficult to secure web applications every year. If your web application is valuable to you and you don't want it to be hacked, you should definitely think about its security if you haven't already. Even a simple website crash can lead to significant downtime, and therefore to loss of customers and profits, let alone hacking.



Main threats

Web security threats to applications caused by their vulnerabilities can be divided into three main types:



XSS attacks , which can content writing service be divided into two more types (read more about this below);

SQL injections ;

Includes , which are divided into local and remote.

In order to know how to behave in case of danger arising from a vulnerability in the security of a web application, it is necessary to understand what the threat is and where it comes from. To understand this, let's study the types of threats described above in more detail.



XSS attacks

This abbreviation translates as cross-site scripting . This method of hacking web applications is used by hackers to insert malicious code into the html of your site. Such malicious JavaScript code, of course, is executed without the knowledge of the site visitor.



With active cross-site scripting, malicious code is saved in web application files and is displayed directly when requests are made to it. The difference with passive cross-site scripting is that the code is not saved on the server, but is transmitted as a GET/POST parameter for display on the page.





The ultimate goal of such attacks is to use a vulnerability to create a malicious link, and after the administrator or user of the resource follows this link, steal their cookies. Many sites and even very large projects are subject to such dangers, so do not underestimate XSS attacks. In order to combat such threats, you need to follow the main rule - make htmlspecialchars fields, and also subject html tags to strict filtering.



SQL injections

This is a type of vulnerability in web application security that allows hackers to change or supplement data in a SQL query with their own, harmful ones. Thanks to this, hackers gain access to almost any resource data and can gain access to the server. Sometimes, attackers even manage to execute PHP code, which will also inevitably lead to loss of data and access to the site. In order to combat this type of vulnerability, there are two basic rules:



First , you must filter quotes in the code, and do it absolutely everywhere: in $_GET, $_POST, $_COOKIES. For example, you can replace “'” with
Secondly , it is highly undesirable to use constructions of this kind in queries: …where id = $id…, instead of them you should use, for example, …where id = '$id', but when the quotes are already filtered, for example, as in the point above.

Includes

With the help of these security vulnerabilities, hackers are able to use the necessary request to display the contents of a third-party resource site inside the attacked one. Thanks to this, the hacker gains access to all the server information by inserting his malicious code, for example, a script that controls all the resource data. The vulnerable code may look something like this:




If such code is executed, all information stored in the main.html file will be displayed on the website page. If the attacker makes another request, for example:




In this case, he will be able to get all the necessary information to access the server. Such an include is called remote. In the absence of a specific server config, such an include can become local, that is, giving access to the contents of all server files.



Conclusion

There are still quite a large number of web application vulnerabilities in addition to those described above, and any resource or application is likely to be susceptible to them. However, by preparing for the three most common threats and getting rid of vulnerabilities, you can ensure web security for your project, as well as its reliable operation. The most important thing is to be prepared for the threat in advance and make all the necessary settings in time to prevent it and eliminate existing vulnerabilities.