CVE-2021-43404 : Exploit Details and Defense Strategies

An issue was discovered in FusionPBX before 4.5.30 where the FAX file name may have risky characters.

Understanding CVE-2021-43404

This CVE involves a vulnerability in FusionPBX version before 4.5.30 that allows risky characters in FAX file names.

What is CVE-2021-43404?

The vulnerability in FusionPBX before version 4.5.30 allows for potentially risky characters in FAX file names, posing a security risk.

The Impact of CVE-2021-43404

The presence of risky characters in FAX file names could potentially lead to security breaches or unauthorized access to sensitive information within FusionPBX systems.

Technical Details of CVE-2021-43404

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The issue in FusionPBX before 4.5.30 permits the existence of risky characters in FAX file names, which can be exploited by attackers.

Affected Systems and Versions

Affected Version: FusionPBX before 4.5.30
Systems: FusionPBX installations running versions prior to 4.5.30

Exploitation Mechanism

Attackers can manipulate FAX file names with risky characters to potentially execute unauthorized actions on vulnerable FusionPBX systems.

Mitigation and Prevention

To address and prevent the CVE-2021-43404 vulnerability, consider the following steps:

Immediate Steps to Take

Update FusionPBX to version 4.5.30 or later to mitigate the risk of having risky characters in FAX file names.
Ensure proper input validation to disallow risky characters in filenames.

Long-Term Security Practices

Regularly monitor FusionPBX systems for any unusual file names or activity.
Educate users on safe file naming conventions and security best practices.

Patching and Updates

Stay informed about security updates for FusionPBX and promptly apply patches to address known vulnerabilities.