Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The Chat Bubble WordPress plugin before 2.3 does not sanitise and escape some contact parameters, which could allow unauthenticated attackers to set Stored Cross-Site Scripting payloads in them, which will trigger when an admin view the related contact message
CWE-79 - Cross Site Scripting
Cross-Site Scripting, commonly referred to as XSS, is the most dominant class of vulnerabilities. It allows an attacker to inject malicious code into a pregnable web application and victimize its users. The exploitation of such a weakness can cause severe issues such as account takeover, and sensitive data exfiltration. Because of the prevalence of XSS vulnerabilities and their high rate of exploitation, it has remained in the OWASP top 10 vulnerabilities for years.