CVE-2021-40542 : Vulnerability Insights and Analysis

OpenSIS-Classic Version 8.0 is affected by a cross-site scripting (XSS) vulnerability that allows an unauthenticated user to inject and execute JavaScript code.

Understanding CVE-2021-40542

This CVE-2021-40542 involves a security issue in OpenSIS-Classic Version 8.0 that enables malicious JavaScript code execution.

What is CVE-2021-40542?

The CVE-2021-40542 vulnerability pertains to OpenSIS-Classic Version 8.0 being susceptible to cross-site scripting (XSS) attacks. These attacks can lead to unauthorized code execution through a specific parameter.

The Impact of CVE-2021-40542

The XSS vulnerability in OpenSIS-Classic Version 8.0 can have severe consequences, allowing attackers to execute arbitrary JavaScript code in the context of the user's browser.

Technical Details of CVE-2021-40542

This section delves into the technical aspects of the CVE-2021-40542 vulnerability.

Vulnerability Description

OpenSIS-Classic Version 8.0 contains a cross-site scripting (XSS) flaw that permits unauthenticated users to insert and run JavaScript code via the link_url parameter in Ajax_url_encode.php.

Affected Systems and Versions

Systems: OpenSIS-Classic Version 8.0
Versions: All versions are affected.

Exploitation Mechanism

The exploitation primarily involves injecting malicious JavaScript code through the link_url parameter in the Ajax_url_encode.php file, taking advantage of the XSS vulnerability.

Mitigation and Prevention

Proactive measures to mitigate the risks associated with CVE-2021-40542.

Immediate Steps to Take

Upgrade OpenSIS-Classic to a patched version that addresses the XSS vulnerability.
Implement proper input validation to prevent script injection.

Long-Term Security Practices

Regularly monitor and audit your web applications for security vulnerabilities.
Educate users about the risks of opening untrusted links to prevent XSS attacks.

Patching and Updates

Apply security patches released by OpenSIS to fix the XSS vulnerability promptly.