This article is a part of our Vulnerability Database (back to index)
Cross-site Scripting occurrences in Calendar
Improper neutralization of input during web page generation ('Cross-site Scripting') vulnerability in Event Management in Synology Calendar before 2.4.5-10930 allows remote authenticated users to inject arbitrary web script or HTML via unspecified vectors. (2022-07-12, CVE-2022-22682)
Cross-site scripting (XSS) vulnerability in Event Editor in Synology Calendar before 2.3.0-0615 allows remote attackers to inject arbitrary web script or HTML via the title parameter. (2019-06-30, CVE-2019-11825)
The Kieran O'Shea Calendar plugin before 1.3.11 for WordPress has Stored XSS via the event_title parameter in a wp-admin/admin.php?page=calendar add action, or the category name during category creation at the wp-admin/admin.php?page=calendar-categories URI. (2019-05-13, CVE-2018-18872)
In Nextcloud Calendar before 1.5.8 and 1.6.1, a missing sanitization of search results for an autocomplete field could lead to a stored XSS requiring user-interaction. The missing sanitization only affected group names, hence malicious search results could only be crafted by privileged users like admins or group admins. (2018-07-05, CVE-2018-3763)
Cross-site scripting (XSS) vulnerability in Notification Center in Synology Calendar before 2.1.1-0502 allows remote authenticated users to inject arbitrary web script or HTML via title parameter. (2018-05-10, CVE-2018-8915)
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>