This article is a part of our Vulnerability Database (back to index)
Cross-site Scripting occurrences in Booking Calendar
The Booking Calendar WordPress plugin before 8.9.2 does not sanitise and escape the booking_type parameter before outputting it back in an admin page, leading to a Reflected Cross-Site Scripting (2022-01-03, CVE-2021-25040)
An issue was discovered in the booking-calendar plugin 2.1.7 for WordPress. XSS exists via the wp-admin/admin.php extra_field1[items][field_item1][price_percent] parameter. (2018-01-13, CVE-2018-5671)
An issue was discovered in the booking-calendar plugin 2.1.7 for WordPress. XSS exists via the wp-admin/admin.php form_field5[label] parameter. (2018-01-13, CVE-2018-5672)
An issue was discovered in the booking-calendar plugin 2.1.7 for WordPress. XSS exists via the wp-admin/admin.php sale_conditions[count][] parameter. (2018-01-13, CVE-2018-5670)
Why Cross-site Scripting can be dangerous
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>