CVE-2021-40219 : Exploit Details and Defense Strategies

Bolt CMS <= 4.2 is vulnerable to Remote Code Execution due to unsafe theme rendering allowing an attacker to inject server-side template code remotely.

Understanding CVE-2021-40219

This CVE involves a significant vulnerability in Bolt CMS that can result in Remote Code Execution if exploited.

What is CVE-2021-40219?

Bolt CMS version <= 4.2 is susceptible to Remote Code Execution. An authenticated attacker can abuse unsafe theme rendering to edit the theme and inject server-side template code, leading to remote code execution.

The Impact of CVE-2021-40219

The vulnerability permits attackers to execute malicious code remotely, potentially compromising the entire system running the vulnerable CMS.

Technical Details of CVE-2021-40219

This section delves into the technical aspects of the CVE.

Vulnerability Description

A flaw in Bolt CMS version <= 4.2 allows authenticated attackers to utilize unsafe theme rendering to introduce server-side template injection, facilitating remote code execution.

Affected Systems and Versions

Affected Version: Bolt CMS <= 4.2
Vendor: n/a
Product: n/a

Exploitation Mechanism

The vulnerability is exploited through injecting malicious server-side template code via theme editing within Bolt CMS.

Mitigation and Prevention

Here are the steps to mitigate the risks associated with CVE-2021-40219.

Immediate Steps to Take

Update Bolt CMS to version 4.3 or later to patch the vulnerability.
Monitor for any unauthorized changes to theme files.
Implement strict access controls to prevent unauthorized access to theme editing.

Long-Term Security Practices

Regularly audit and review themes and templates for any malicious modifications.
Educate users and administrators on secure coding practices and the risks associated with theme editing.

Patching and Updates

Apply security patches promptly as released by the Bolt CMS team.
Stay informed about security best practices and updates from the CMS provider.