What happened
Published August 1, 2026 (CVSS 8.8/High). The AI Engine plugin — which bundles a WordPress chatbot, AI framework integration, and MCP server — fails to validate CSRF nonces in its OAuth-style reauthorization endpoint, letting an attacker forge a request that creates a rogue admin account when a real administrator's browser executes it.
Why it matters
AI Engine is one of the most widely installed WordPress AI/chatbot/MCP plugins; a successful CSRF exploit yields full administrative control of the WordPress site and its connected AI/MCP configuration (API keys, connected models, chatbot data), giving attackers a foothold to pivot into any backend systems the site's AI integrations touch.
Attack vector
Missing/incorrect nonce validation in the `reauth_for_authorize` function allows an unauthenticated attacker to craft a CSRF request that tricks a logged-in site administrator into creating a new administrator account with attacker-supplied credentials, granting full site takeover.
Affected systems
AI Engine – The Chatbot, AI Framework & MCP for WordPress, all versions up to and including 3.6.5
Mitigation
Update AI Engine to version 3.6.6 or later.