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 should be patched in version 1.1.7. Any version earlier than this is vulnerable.
A partial work around is to free the Object prototype:
Object.freeze(Object.prototype)
{
"severity": "CRITICAL",
"nvd_published_at": "2021-09-27T18:15:00Z",
"cwe_ids": [
"CWE-1321",
"CWE-915"
],
"github_reviewed_at": "2021-09-27T19:18:37Z",
"github_reviewed": true
}