CVE-2021-39349 : Exploit Details and Defense Strategies

The Author Bio Box WordPress plugin up to and including version 3.3.1 is vulnerable to Stored Cross-Site Scripting (XSS) due to insufficient input validation and sanitization, allowing attackers with administrative user access to inject arbitrary web scripts.

Understanding CVE-2021-39349

This CVE represents an Authenticated Stored Cross-Site Scripting vulnerability in the Author Bio Box plugin.

What is CVE-2021-39349?

The CVE-2021-39349 vulnerability in the Author Bio Box plugin allows attackers with administrative user access to insert malicious web scripts due to inadequate input validation and sanitization.

The Impact of CVE-2021-39349

This vulnerability poses a medium severity risk based on CVSS score 5.5, compromising the integrity of affected systems and potentially exposing user confidentiality.

Technical Details of CVE-2021-39349

The technical aspects of the CVE provide deeper insights into the vulnerability.

Vulnerability Description

The vulnerability is classified as CWE-79 Cross-site Scripting (XSS).
Attack complexity is low, requiring high privileges, and has a network-based attack vector.

Affected Systems and Versions

Product: Author Bio Box
Vendor: Author Bio Box
Versions affected: <= 3.3.1

Exploitation Mechanism

Attackers can exploit this vulnerability through several parameters in the 'class-author-bio-box-admin.php' file.
Multi-site installations where 'unfiltered_html' is disabled for administrators are at risk.

Mitigation and Prevention

Protecting against CVE-2021-39349 involves immediate actions and long-term security measures.

Immediate Steps to Take

Uninstall the Author Bio Box plugin from the WordPress site.

Long-Term Security Practices

Regularly update plugins and WordPress installations.
Implement strict input validation and sanitization practices.

Patching and Updates

Source: Wordfence
Additional References: GitHub, WordPress Plugin Changeset