Affected: HumanSignal label-studio
Label Studio is a multi-type data labeling and annotation tool. In 1.22.0 and earlier, a persistent stored cross-site scripting (XSS) vulnerability exists in the custom_hotkeys functionality of the application. An authenticated attacker (or one who can trick a user/administrator into updating their custom_hotkeys) can inject JavaScript code that executes in other users’ browsers when those users load any page using the templates/base.html template. Because the application exposes an API token endpoint (/api/current-user/token) to the browser and lacks robust CSRF protection on some API endpoints, the injected script may fetch the victim’s API token or call token reset endpoints — enabling full account takeover and unauthorized API access.
Affected: PyPI: label-studio
### Prologue
These vulnerabilities have been found and chained by DCODX-AI. Validation of the exploit chain has been confirmed manually.
### Summary
A persistent stored cross-site scripting (XSS) vulnerability exists in the custom_hotkeys functionality of the application. An authenticated attacker (or one who can trick a user/administrator into updating their custom_hotkeys) can inject JavaScript code that executes in other users’ browsers when those users load any page using the `templates/base.html` template. Because the application exposes an API token endpoint (`/api/current-user/token`) to the browser and lacks robust CSRF protection on some API endpoints, the injected script may fetch the victim’s API token or call token reset endpoints — enabling full account takeover and unauthorized API access. This vulnerability is of critical severity due to the broad impact, minimal requirements for exploitation (authenticated user), and the ability to escalate privileges to full account compromise.
### Details Within `templates/base.html`, the application renders user-controlled hotkey configuration via the following JavaScript snippet:
```js var __customHotkeys = {{ user.custom_hotkeys|json_dumps_ensure_ascii|safe }}; ``` Here, user.custom_hotkeys is run through json_dumps_ensure_ascii (in `core/templatetags/filters.py`) which performs `json.dumps(dictionary, ensure_ascii=False)` but does not escape closing `</script>` sequences or other dangerous characters. Because the…