Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The sanitisation step of the Safe SVG WordPress plugin before 1.9.10 can be bypassed by spoofing the content-type in the POST request to upload a file. Exploiting this vulnerability, an attacker will be able to perform the kinds of attacks that this plugin should prevent (mainly XSS, but depending on further use of uploaded SVG files potentially other XML attacks).
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.