WordPress · Book A Room Event Calendar · CVE-2026-9721
**Name of the Vulnerable Software and Affected Versions**
Book a Room Event Calendar versions prior to 2.0
**Description**
The Book a Room Event Calendar plugin for WordPress is subject to Cross-Site Request Forgery (CSRF), a flaw where an attacker tricks a victim into performing an action they did not intend to. The issue exists in the `settings form()` and `update settings()` functionality due to missing or incorrect nonce validation. A nonce is a unique token used to verify that a request was intentionally sent by the user. The plugin's options page handler uses the `action` POST parameter to call `update settings()`, which saves configuration details—including the external database host, username, password, prefix, database name, encryption key, and registration page URL—via `update option()`. Because the plugin fails to generate or verify nonces, unauthenticated attackers can modify these database connection settings by tricking a site administrator into clicking a malicious link.
**Recommendations**
Update the plugin to a version later than 1.9.
As a temporary workaround, restrict access to the plugin settings page to only essential administrators until the update is applied.