Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The Simple:Press plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'postitem' parameter manipulated during a forum response in versions up to, and including, 6.8 due to insufficient input sanitization and output escaping that makes injecting object and embed tags possible. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages when responding to forum threads that will execute whenever a user accesses an injected page.
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.