GHSA-jr3j-whm4-9wwm

### Overview

Versions before and including `11.30.0` are vulnerable to reflected XSS. An attacker can execute arbitrary code when the library's - `flashMessage` feature is utilized and user input or data from URL parameters is incorporated into the `flashMessage`. - `languageDictionary` feature is utilized and user input or data from URL parameters is incorporated into the `languageDictionary`.

### Am I affected? You are affected by this vulnerability if you are using `auth0-lock` version `11.30.0` or lower and all of the following conditions apply:

- You are utilizing `flashMessage` feature. - User input or data from URL parameters is incorporated into the `flashMessage`.

An example of a vulnerable snippet where query parameters are used to populate the `text` property of a `flashMessage`. ```js var params = new URLSearchParams(location.search); var errorMessage = params.get('error__message'); var showParams = {};

if (!!errorMessage === true) { showParams.flashMessage = { type: 'error', text: 'We were unable to log you in. ' + errorMessage, }; }

lock.show(showParams); ```

OR

- You are utilizing `languageDictionary` feature. - User input or data from URL parameters is used in `languageDictionary` properties.

An example of a vulnerable snippet where query parameters are used to populate the `socialLoginInstructions` property of a `languageDictionary`. ```js var params = new URLSearchParams(location.search); var instruction = params.get('instruction');

var options = { languageDictionary: { emailInputPlaceholder: "something@youremail.com", title: "title", socialLoginInstructions: instruction }, };

var lock = new Auth0LockPasswordless( CLIENT_ID, DOMAIN, options );

lock.show() ```

### How to fix that? Upgrade to version `11.30.1`.

### Will this update impact my users? The fix uses [DOMPurify](https://github.com/cure53/DOMPurify) to sanitise the `flashMessage` and `languageDictionary` inputs. If you are including inline JavaScript in these fields, like `script` tags or `onclick` attributes, these will be removed.