CVE-2021-38157 : Vulnerability Insights and Analysis

LeoStream Connection Broker 9.x before 9.0.34.3 is vulnerable to Unauthenticated Reflected Cross-Site Scripting (XSS) through the /index.pl user parameter. This exploit can be executed remotely without authentication. It's essential to understand the impact and mitigation strategies associated with this CVE.

Understanding CVE-2021-38157

LeoStream Connection Broker 9.x before version 9.0.34.3 contains a security flaw that allows an attacker to perform XSS attacks through the user parameter in /index.pl without the need for authentication.

What is CVE-2021-38157?

The CVE-2021-38157 vulnerability affects LeoStream Connection Broker 9.x versions prior to 9.0.34.3. It enables unauthenticated malicious users to inject and execute arbitrary scripts in the context of the victim's browser.

The Impact of CVE-2021-38157

This vulnerability poses a severe security risk as attackers can launch XSS attacks, potentially leading to unauthorized access to sensitive data, session hijacking, defacement of web pages, and other malicious activities.

Technical Details of CVE-2021-38157

LeoStream Connection Broker 9.x before 9.0.34.3 suffers from Unauthenticated Reflected XSS, specifically via the /index.pl user parameter. The maintainer no longer supports products affected by this vulnerability.

Vulnerability Description

The security issue in LeoStream Connection Broker allows unauthenticated attackers to inject client-side scripts into web pages viewed by other users.

Affected Systems and Versions

This vulnerability impacts LeoStream Connection Broker version 9.x before 9.0.34.3. Systems running these versions are at risk of exploitation.

Exploitation Mechanism

Malicious actors can exploit this vulnerability by inserting malicious scripts into the /index.pl user parameter, which are then executed when a user interacts with the affected page.

Mitigation and Prevention

It's crucial to take immediate steps to secure systems and prevent exploitation of CVE-2021-38157.

Immediate Steps to Take

Upgrade LeoStream Connection Broker to version 9.0.34.3 or later to mitigate the vulnerability.
Avoid clicking on suspicious links or visiting untrusted websites to reduce the risk of XSS attacks.

Long-Term Security Practices

Regularly update and patch all software to ensure protection against known vulnerabilities.
Implement web application firewalls and input validation mechanisms to filter and sanitize user inputs.

Patching and Updates

Stay informed about security updates and advisories from LeoStream to deploy patches promptly and secure your systems against potential exploits.