CVE-2018-19420 : What You Need to Know

Get insights into the security vulnerability in GetSimpleCMS version 3.3.15 that allows the execution of HTML code through specific file upload scenarios.

Understanding CVE-2018-19420

In version 3.3.15 of GetSimpleCMS, a vulnerability exists that enables the execution of HTML code despite restrictions on uploading .html files in admin/upload.php.

What is CVE-2018-19420?

The issue arises from alternative scenarios where HTML code execution is possible, such as files with no extensions or unrecognized extensions like 'test' or 'test.asdf'. This loophole is due to specific files and functions within the CMS.

The Impact of CVE-2018-19420

This vulnerability can lead to potential security breaches, allowing malicious actors to upload and execute harmful HTML code on the affected system.

Technical Details of CVE-2018-19420

Explore the specifics of this security flaw in GetSimpleCMS version 3.3.15.

Vulnerability Description

The vulnerability in admin/upload.php allows for the execution of HTML code through files with no extensions or unrecognized extensions, bypassing the .html upload restriction.

Affected Systems and Versions

Product: GetSimpleCMS
Version: 3.3.15

Exploitation Mechanism

The presence of admin/upload-uploadify.php and the function validate_safe_file in admin/inc/security_functions.php facilitates the execution of HTML code through specific file upload scenarios.

Mitigation and Prevention

Discover the steps to mitigate and prevent exploitation of CVE-2018-19420.

Immediate Steps to Take

Disable file uploads with unrecognized extensions.
Regularly monitor and review uploaded files for suspicious content.
Implement file type verification mechanisms.

Long-Term Security Practices

Keep GetSimpleCMS and its components up to date.
Conduct regular security audits and penetration testing.

Patching and Updates

Apply patches and updates provided by GetSimpleCMS to address this vulnerability.