Leaflet Map Cross-site Scripting

The Leaflet Map WordPress plugin before 3.0.0 does not verify the CSRF nonce when saving its settings, which allows attackers to make a logged in admin update the settings via a Cross-Site Request Forgery attack. This could lead to Cross-Site Scripting issues by either changing the URL of the JavaScript library being used, or using malicious attributions which will be executed in all page with an embed map from the plugin (2021-08-09, CVE-2021-24467)

The Leaflet Map WordPress plugin before 3.0.0 does not escape some shortcode attributes before they are used in JavaScript code or HTML, which could allow users with a role as low as Contributors to exploit stored XSS issues (2021-08-02, CVE-2021-24468)

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>