CVE-2021-28115 : What You Need to Know

The OUGC Feedback plugin before 1.8.23 for MyBB is vulnerable to a cross-site scripting (XSS) attack via the comment field of feedback during an edit operation.

Understanding CVE-2021-28115

This section will provide insights into the impact, technical details, and mitigation strategies related to CVE-2021-28115.

What is CVE-2021-28115?

The CVE-2021-28115 vulnerability arises in the OUGC Feedback plugin versions prior to 1.8.23 for the MyBB forum software. Attackers can exploit this security flaw by injecting malicious scripts into the comment field of feedback while performing an edit operation.

The Impact of CVE-2021-28115

The impact of this vulnerability is the potential execution of arbitrary scripts within the context of the victim's browser. This can lead to various attacks, including stealing sensitive information, session hijacking, or defacing the affected website.

Technical Details of CVE-2021-28115

Let's delve into the technical aspects of CVE-2021-28115 to understand the vulnerability better.

Vulnerability Description

The vulnerability allows threat actors to insert malicious scripts into the feedback comment field during an edit operation, which are then executed when viewed by other users, leading to XSS attacks.

Affected Systems and Versions

The OUGC Feedback plugin versions before 1.8.23 for MyBB are affected by this vulnerability. Users who have not updated to the patched version are at risk.

Exploitation Mechanism

An attacker can exploit this vulnerability by crafting a specially designed comment containing malicious scripts and submitting it during an edit operation in the feedback section of the MyBB forum powered by the OUGC Feedback plugin.

Mitigation and Prevention

Understanding how to mitigate and prevent the exploitation of CVE-2021-28115 is crucial for ensuring the security of MyBB forums.

Immediate Steps to Take

Forum administrators should promptly update the OUGC Feedback plugin to version 1.8.23 or above to mitigate the risk of exploitation. Additionally, users should refrain from interacting with suspicious feedback comments.

Long-Term Security Practices

Implementing a Content Security Policy (CSP) can help prevent XSS attacks by restricting the sources from which certain types of content can be loaded on a website.

Patching and Updates

Regularly check for security updates and patches released by the plugin developers and MyBB platform to address known vulnerabilities and enhance the overall security posture of the forum.