mod_security Bug Fix and Enhancement Update

mod_security Updated 02 Oct 2025

Summary

18/05/2021
N/A
Yes i
Unrated
Not published

ALEA-2021:1833: mod_security bug fix and enhancement update. Affects mod_security versions < 2.9.2-9.el8. Fixed in 2.9.2-9.el8. How to fix ↓

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Background

mod_security is a web application firewall module for Apache HTTP Server. It provides protection against various attacks, including SQL injection, cross-site scripting (XSS), and remote file inclusion. The module analyzes HTTP requests and responses, applying rules to detect and prevent malicious activity. This vulnerability affects mod_security versions prior to 2.9.2-9.el8 on AlmaLinux 8.

Vulnerability Detail

This vulnerability in mod_security allows attackers to bypass security restrictions and potentially execute malicious code on the server. The issue originates from a flaw in the module's input handling, which can be exploited to evade detection and perform unauthorized actions. An attacker could craft specially crafted requests to exploit this vulnerability, leading to various consequences such as data breaches, server compromise, or unauthorized access to sensitive information.

How To Fix

Minimum fixed version

2.9.2-9.el8

This is the first release that contains the fix.

sudo dnf update mod_security

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Workaround

There is no known workaround for this vulnerability. It is essential to apply the recommended update to ensure the security of the system.

Conclusion

The mod_security bug fix and enhancement update addresses a vulnerability that allows attackers to bypass security restrictions and potentially execute malicious code on the server. It is crucial to update mod_security to version 2.9.2-9.el8 or later to ensure the security of the system. For further support on vulnerability remediation, contact DevNack.com.

See every vulnerability recorded for mod_security →

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FAQ

mod_security is a web application firewall module for Apache HTTP Server. It provides protection against various attacks, including SQL injection, cross-site scripting (XSS), and remote file inclusion.

This vulnerability allows attackers to bypass security restrictions and potentially execute malicious code on the server, leading to data breaches, server compromise, or unauthorized access to sensitive information.

To fix this vulnerability, update mod_security to version 2.9.2-9.el8 or later. Refer to the AlmaLinux Release Notes for instructions on obtaining and applying the update.

No, there is no known workaround for this vulnerability. It is crucial to apply the recommended update to mitigate the risk.

You can find more information about this vulnerability in the AlmaLinux Release Notes and the advisory linked in the References section.

Related vulnerabilities

Recent vulnerabilities recorded for mod_security.

How To Fix

Minimum fixed version

2.9.2-9.el8

This is the first release that contains the fix.

sudo dnf update mod_security

Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →

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