WordPress Grand Blog theme <= 3.1 - Cross Site Request Forgery (CSRF) vulnerability

A successful CSRF attack could allow an attacker to modify blog posts, delete content, change user settings, or perform other administrative actions as the logged-in user. The impact is particularly severe if the targeted user has administrative privileges, as this could grant the attacker full control over the WordPress site. This vulnerability is similar to other CSRF flaws where user interaction is required, but the attacker can leverage social engineering or malicious websites to trigger the unwanted actions. The blast radius extends to any user with access to the affected plugin.

Websites using the Grand Blog WordPress plugin, particularly those with administrative users who frequently interact with the plugin's features, are at risk. Shared hosting environments where multiple WordPress sites share the same server resources could also be affected, as a compromise of one site could potentially lead to the exploitation of others.

• wordpress / composer / npm:

grep -r 'grandblog_settings_update' /var/www/html/wp-content/plugins/

• generic web:

curl -I https://your-wordpress-site.com/wp-content/plugins/grandblog/ | grep -i 'csrf-token'

1. 2026-04-08Disclosure

   disclosure

1. Reserviert2026-04-07
2. Veröffentlicht2026-04-08
3. Geändert2026-04-29
4. EPSS aktualisiert2026-04-15

The primary mitigation for CVE-2026-39632 is to upgrade to a patched version of the Grand Blog plugin as soon as it becomes available. Until a patch is released, consider implementing temporary workarounds such as adding CSRF tokens to all sensitive forms and actions within the plugin. Web Application Firewalls (WAFs) can be configured to filter out suspicious requests that exhibit CSRF characteristics. Regularly review user activity logs for any unusual or unauthorized actions.