CVE-2021-24856 Explained : Impact and Mitigation

This article provides detailed information about CVE-2021-24856, a vulnerability in the Shared Files WordPress plugin before version 1.6.61 that could lead to stored Cross-Site Scripting attacks.

Understanding CVE-2021-24856

CVE-2021-24856, also known as "Shared Files < 1.6.61 - Admin+ Stored Cross-Site Scripting," affects the Shared Files WordPress plugin. The vulnerability arises from unsanitized and unescaped settings, enabling privilege escalation for attackers.

What is CVE-2021-24856?

The Shared Files WordPress plugin version before 1.6.61 fails to adequately sanitize the Download Counter Text settings. This oversight can be exploited by high-privilege users to execute Cross-Site Scripting attacks, regardless of the unfiltered_html capability settings.

The Impact of CVE-2021-24856

This vulnerability could allow malicious actors with high privileges to inject and execute malicious scripts, leading to potential data theft, account takeover, and unauthorized actions on affected websites.

Technical Details of CVE-2021-24856

The following technical aspects outline the vulnerability:

Vulnerability Description

The flaw in the Shared Files plugin lies in its failure to properly handle the Download Counter Text settings, enabling attackers to inject malicious scripts into the site.

Affected Systems and Versions

The vulnerability affects Shared Files WordPress plugin versions prior to 1.6.61.

Exploitation Mechanism

Attackers can leverage this vulnerability by manipulating the Download Counter Text settings to inject and execute malicious scripts on the target WordPress site.

Mitigation and Prevention

To address CVE-2021-24856 and enhance overall security measures, consider the following steps:

Immediate Steps to Take

Update the Shared Files plugin to version 1.6.61 or later to mitigate the vulnerability.
Monitor user inputs and sanitize all text fields to prevent arbitrary code execution.

Long-Term Security Practices

Regularly audit and review plugins and themes for security vulnerabilities.
Enforce the principle of least privilege for user roles to limit the impact of potential compromises.

Patching and Updates

Stay informed about security patches and updates for all installed plugins and themes. Promptly apply patches released by developers to eliminate known vulnerabilities.