Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Bugzilla 2.20rc1 through 2.20 and 2.21.1, when using RSS 1.0, allows remote attackers to conduct cross-site scripting (XSS) attacks via a title element with HTML encoded sequences such as ">", which are automatically decoded by some RSS readers. NOTE: this issue is not in Bugzilla itself, but rather due to design or documentation inconsistencies within RSS, or implementation vulnerabilities in RSS readers. While this issue normally would not be included in CVE, it is being identified since the Bugzilla developers have addressed it.
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.