Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The dsgvoaio_write_log AJAX action of the DSGVO All in one for WP WordPress plugin before 4.0 did not sanitise or escape some POST parameter submitted before outputting them in the Log page in the administrator dashboard (wp-admin/admin.php?page=dsgvoaiofree-show-log). This could allow unauthenticated attackers to gain unauthorised access by using an XSS payload to create a rogue administrator account, which will be trigged when an administrator will view the logs.
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.