The HTMLSanitizer class in html-sanitizer.ts in all released versions of the Aurelia framework 1.x repository is vulnerable to XSS. The sanitizer only attempts to filter SCRIPT elements, which makes it feasible for remote attackers to conduct XSS attacks via (for example) JavaScript code in an attribute of various other elements. An attacker might also exploit a bug in how the SCRIPT string is processed by splitting and nesting them for example.

aurelia-path is part of the Aurelia platform and contains utilities for path manipulation. There is a prototype pollution vulnerability in aurelia-path before version 1.1.7. The vulnerability exposes Aurelia application that uses `aurelia-path` package to parse a string. The majority of this will be Aurelia applications that employ the `aurelia-router` package. An example is this could allow an attacker to change the prototype of base object class `Object` by tricking an application to parse the following URL: `https://aurelia.io/blog/?__proto__[asdf]=asdf`. The problem is patched in version `1.1.7`.