Quark Drive before 0.8.5 contains a stored cross-site scripting vulnerability in the System Configuration page where the template renders push_config key names using Vue.js's v-html directive without escaping. Authenticated attackers can inject HTML or JavaScript payloads as key names through the POST /update endpoint, which are persisted to disk and executed in the browsers of all authenticated users accessing the System Configuration tab, allowing session cookie exfiltration and arbitrary authenticated actions.