How to Hide Apache Version Number and Other Sensitive Info?

Introduction

Cybersecurity is a growing concern for businesses and individuals alike. One way to protect yourself against potential attacks is by hiding sensitive information such as your Apache version number. The Apache version number can be used by attackers to identify vulnerabilities in your system and launch an attack.

Additionally, default Apache settings may reveal sensitive information such as server operating system, installed modules, or applications, which can make it easier for hackers to gain unauthorized access. By hiding the Apache version number and other sensitive information, you can reduce the risk of cyberattacks.

Understanding Apache Version Number and Sensitive Information

What is Apache Version Number?

Before we dive into the topic of sensitive information, let's first talk about what Apache version number is. Apache version number is a string of numbers and letters that indicates the version of the Apache web server software running on a server. This information can be easily obtained by an attacker by simply sending a request to the server asking for this information.

Why is it Sensitive?

Apache version number can be used by attackers to identify vulnerabilities in old or outdated versions of the software. For instance, if an attacker knows that a particular version has a known vulnerability, they can use that knowledge to exploit that vulnerability and gain unauthorized access to the server. Therefore, it's crucial to hide this information from prying eyes as much as possible.

Other Sensitive Information Revealed by Default Apache Settings

Apart from Apache version number, there are other pieces of sensitive information that can be revealed by default Apache settings. This includes details such as server operating system type and version, installed modules, directory listing enabled or disabled status etc.

The operating system type and version details can be used by attackers to identify specific exploits that could work against that particular OS. Knowing which modules are installed on the server can also provide attackers with valuable insight into how they might attack your server.

Methods for Hiding Apache Version Number and Other Sensitive Information

Editing httpd.conf file

One of the most common and straightforward methods for hiding Apache version number and other sensitive information is by editing the httpd.conf file. This file contains all the configuration settings for Apache, including those related to security and information disclosure. The following are some steps to follow when editing the httpd.conf file −

• Locate the httpd.conf file on your server. The location of this file may differ depending on your server setup, but it is usually located in /etc/httpd/conf or /usr/local/apache2/conf.

• Open the httpd.conf file using a text editor such as nano or vi.

• Search for "ServerTokens" in the file.

  This directive specifies what information about Apache should be included in HTTP response headers, such as server version number and operating system details.

• Change the value associated with ServerTokens from "Full" to "Prod".

  This will remove detailed version number information from HTTP response headers.

• Optionally, you can also change the value associated with ServerSignature from "On" to "Off".

This will prevent Apache from appending a footer line containing server signature details at the end of error pages. 6. Save your changes to httpd.conf and restart Apache using a command such as service apache2 restart or systemctl restart httpd.service.

Using server tokens directive

The ServerTokens directive mentioned earlier can be used to hide sensitive information by specifying different settings depending on what you want to reveal in HTTP response headers −

• ServerTokens Prod −Shows only minimal product information in headers (e.g., "Apache")

• ServerTokens Major −Shows major version number (e.g., "Apache/2")

• ServerTokens Minor −Shows minor version number (e.g., "Apache/2.4")

• ServerTokens Min −Shows minimal information about the server (e.g., "Apache")

To use this directive, you can add it to your httpd.conf file and specify the desired value. For example, if you want to show only minimal product information in headers, you can add the following line −

Using third-party modules

Another way to hide sensitive information is by using third-party modules that provide extra security features. These modules can be installed and configured on your server, often without requiring any major changes to your existing setup. Some popular examples include −

• ModSecurity − A web application firewall that provides protection against various attacks such as SQL injection and cross-site scripting. It can also be configured to remove sensitive information from HTTP response headers.

• mod_evasive −A module that provides protection against DoS (Denial of Service) attacks by limiting the number of requests a client can make within a certain time frame. It can also block clients based on their IP address or other factors.

• mod_headers −A module that allows you to modify HTTP request and response headers according to various rules. This can be useful for removing sensitive information or adding custom headers for security purposes.

To use these modules, you need to install them on your server and configure them according to your needs. Consult the documentation provided with each module for specific instructions on how to do this.

Additional Security Measures for Hiding Sensitive Information

Enabling SSL/TLS Encryption: Protecting Sensitive Information in Transit

While hiding Apache version number and other sensitive information is important, it's also essential to protect the information that is transmitted between the server and clients. This is where Secure Sockets Layer (SSL) or Transport Layer Security (TLS) encryption comes into play.

SSL/TLS encryption encrypts all data that is transmitted between the client and server, making it unreadable to anyone who intercepts it. To enable SSL/TLS encryption, you'll need to obtain an SSL/TLS certificate from a trusted Certificate Authority (CA).

The certificate validates your domain and creates an encrypted connection between your server and clients. Once you've obtained a certificate, you can configure your Apache server to use it.

Implementing Access Controls: Restricting Access to Sensitive Information

Another way to add an extra layer of security when hiding sensitive information on an Apache server is by implementing access controls. Access controls restrict access to certain files or directories based on user credentials or IP addresses. By implementing access controls, you can ensure that only authorized users can access information that may be sensitive.

There are a variety of ways in which you can implement access controls on your Apache server. One common method is through the use of .htaccess files, which allows you to specify authorization rules for specific directories or files.

Conclusion

It is crucial to hide Apache version number and other sensitive information because these details can be used by hackers to exploit vulnerabilities in the web server. By default, Apache reveals this information in its HTTP response headers, which makes it easy for attackers to identify the software version and underlying operating system. This information can then be used to launch targeted attacks that exploit known vulnerabilities in specific versions of Apache or its associated software.