I, Librarian is an open-source version of a PDF managing SaaS. Supplemental Files are allowed to be viewed in the browser, only if they have a white-listed MIME type. Unfortunately, this logic is broken, thus allowing unsafe files containing Javascript to be executed with the application context. An attacker can exploit this vulnerability by uploading a supplementary file that contains a malicious code or script. This code will then be executed when the file is loaded in the browser. The vulnerability was fixed in version 5.11.2.
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as "<", ">", and "&" that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages.