Auth bypass in Tigroumeow Ai Engine – Mcp Server & Chatbot For WordPress, With Claude, Chatgpt Gemini
CVE-2026-110732
The AI Engine – The Chatbot, AI Framework & MCP for WordPress plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 3.8.6 This is due to the MCP module's OAuth 2.1 Dynamic Client Registration endpoint (/wp-json/mcp/v1/oauth/register) being registered with a permission_callback of __return_true, allowing an unauthenticated user to register an active OAuth client with an attacker-controlled redirect URI. This makes it possible for unauthenticated attackers to obtain an administrator-bound MCP access token, and thereby full administrator-level control through the MCP tools (including user creation and option updates), once an administrator approves the attacker's client on the OAuth consent screen. The consent page is additionally served without X-Frame-Options or Content-Security-Policy frame-ancestors, so that approval can be obtained via clickjacking.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.003 (19.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 20th percentile — 19.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
The 30-day trend appears once there are two daily scores.
Affected products
Weakness classification (CWE)
References
- www.wordfence.com/threat-intel/vulnerabilities/id/eb115a8a-35f8-426f-bb67-4a523…
- plugins.trac.wordpress.org/browser/ai-engine/tags/3.8.3/labs/mcp-oauth.php
- plugins.trac.wordpress.org/browser/ai-engine/tags/3.8.3/labs/mcp-oauth.php
- plugins.trac.wordpress.org/browser/ai-engine/tags/3.8.3/labs/mcp-oauth.php
- plugins.trac.wordpress.org/browser/ai-engine/tags/3.8.3/labs/mcp-oauth.php
- plugins.trac.wordpress.org/browser/ai-engine/tags/3.8.3/labs/mcp.php
- plugins.trac.wordpress.org/changeset
- plugins.trac.wordpress.org/changeset/3760851/ai-engine/trunk/labs/mcp-oauth.php
Frequently asked questions
- What is CVE-2026-110732?
- CVE-2026-110732 is a high-severity vulnerability in Tigroumeow Ai Engine – Mcp Server & Chatbot For WordPress, With Claude, Chatgpt Gemini, classified under Missing Authorization. CVSS score: 7.5/10. Published 2026-10-30.
- How severe is CVE-2026-110732?
- High severity. CVSS v3 base score is 7.5 out of 10.