CVE-2021-27949 : Exploit Details and Defense Strategies

A Cross-site Scripting vulnerability was identified in MyBB before version 1.8.26 through Custom moderator tools.

Understanding CVE-2021-27949

This CVE-2021-27949 pertains to a Cross-site Scripting vulnerability that exists in MyBB before version 1.8.26, specifically through Custom moderator tools.

What is CVE-2021-27949?

CVE-2021-27949 is a security vulnerability classified as Cross-site Scripting, allowing malicious actors to execute scripts in the victim's browser.

The Impact of CVE-2021-27949

Exploitation of this vulnerability could result in unauthorized script execution, potentially leading to data theft, user impersonation, or content manipulation.

Technical Details of CVE-2021-27949

This section outlines the technical specifics of the CVE-2021-27949 vulnerability.

Vulnerability Description

The vulnerability enables attackers to inject malicious scripts into web pages viewed by other users, compromising their data and session security.

Affected Systems and Versions

MyBB versions earlier than 1.8.26 are susceptible to this Cross-site Scripting flaw when utilizing Custom moderator tools.

Exploitation Mechanism

Attackers can craft specially designed scripts that, when executed, can interact with the MyBB application within a victim's browser, leading to unauthorized actions.

Mitigation and Prevention

Discover how to protect systems and mitigate the risks associated with CVE-2021-27949.

Immediate Steps to Take

Users are advised to upgrade their MyBB installations to version 1.8.26 or later to address this vulnerability. Additionally, keeping systems up-to-date with security patches is crucial.

Long-Term Security Practices

Implementing input sanitization, output encoding, and regular security audits can help safeguard against Cross-site Scripting attacks.

Patching and Updates

Regularly monitor and apply security updates provided by MyBB to ensure ongoing protection against known vulnerabilities.