XSS in Stackposts - Social Marketing Tool

Improper Neutralization of Input During Web Page Generation vulnerability in Stackposts Social Marketing Tool allows Cross-site Scripting (XSS) attack. By submitting the payload in the username during registration, it can be executed later in the application panel. This could lead to the unauthorised acquisition of information (e.g. cookies from a logged-in user). After multiple attempts to contact the vendor we did not receive any answer. Our team has confirmed the existence of this vulnerability. We suppose this issue affects Social Marketing Tool in all versions.