Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The XPCSafeJSObjectWrapper class in the SafeJSObjectWrapper (aka SJOW) implementation in Mozilla Firefox before 3.5.12, Thunderbird before 3.0.7, and SeaMonkey before 2.0.7 does not properly restrict scripted functions, which allows remote attackers to bypass the Same Origin Policy and conduct cross-site scripting (XSS) attacks via a crafted function.
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.