CVE-2026-9721 Book a Room Event Calendar <= 1.9 - Cross-Site Request Forgery to Settings Update
Attackers can trick administrators into modifying plugin database settings via CSRF, potentially compromising data integrity and security.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-9721?
CVE-2026-9721 is a medium-severity vulnerability in chuhpl Book a Room Event Calendar, published on 24 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
The Book a Room Event Calendar plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 1.9. This is due to missing or incorrect nonce validation on the settings_form()/update_settings() functionality. The plugin's options page handler dispatches on the 'action' POST parameter and calls update_settings(), which persists plugin configuration (including the external database host, username, password, prefix, database name, encryption key, and registration page URL) via update_option(), without ever generating a nonce field in the settings form or verifying one (no wp_nonce_field(), check_admin_referer(), or wp_verify_nonce() exists anywhere in the plugin). This makes it possible for unauthenticated attackers to modify the plugin's database connection settings via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.
Weakness: CWE-352
Which versions are affected by CVE-2026-9721?
How do I fix CVE-2026-9721?
No fix has been published for CVE-2026-9721 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-9721 being exploited?
There is no known exploitation of CVE-2026-9721 in the wild and no public exploit code.
Sources
Also known as GHSA-pfhp-jm8f-gx6g.