Wikidata Query Gui Cross-site Scripting

In Wikibase Wikidata Query Service GUI before 0.3.6-SNAPSHOT 2019-11-07, when mathematical expressions in results are displayed directly, arbitrary JavaScript execution can occur, aka XSS. This was addressed by introducing MathJax as a new mathematics rendering engine. NOTE: this GUI code is no longer bundled with the Wikibase Wikidata Query Service snapshots, such as 0.3.6-SNAPSHOT. (2019-11-27, CVE-2019-19329)

ui/editor/tooltip/Rdf.js in Wikibase Wikidata Query Service GUI before 0.3.6-SNAPSHOT 2019-11-07 allows HTML injection in tooltips for entities. NOTE: this GUI code is no longer bundled with the Wikibase Wikidata Query Service snapshots, such as 0.3.6-SNAPSHOT. (2019-11-27, CVE-2019-19328)

ui/ResultView.js in Wikibase Wikidata Query Service GUI before 0.3.6-SNAPSHOT 2019-11-07 allows HTML injection when reporting the number of results and number of milliseconds. NOTE: this GUI code is no longer bundled with the Wikibase Wikidata Query Service snapshots, such as 0.3.6-SNAPSHOT. (2019-11-27, CVE-2019-19327)

Cross site scripting is an attack where a web page executes code that is injected by an adversary. It usually appears, when users input is presented. This attack can be used to impersonate a user, take over control of the session, or even steal API keys.

The attack can be executed e.g. when you application injects the request parameter directly into the HTML code of the page returned to the user:

https://server.com/confirmation?message=Transaction+Complete

what results in:

<span>Confirmation: Transaction Complete</span>

In that case the message can be modified to become a valid Javascript code, e.g.:

https://server.com/confirmation?message=<script>dangerous javascript code here</script>

and it will be executed locally by the user's browser with full access to the user's personal application/browser data:

<span>Confirmation: <script>dangerous javascript code here</script></span>