WP-Chatbot for Messenger <= 4.9 - Missing Authorization to Unauthenticated Chatbot Configuration Takeover
Strategic Overview
- Status
- Unpatched
- Affected Plugin
- WP-Chatbot for Messenger
- Affected Version
<= 4.9- CVSS
- 5.3Medium
- Weakness type
- CWE-862 · Missing Authorization
- CVE
CVE-2026-3506
At a glance
CVE-2026-3506 is a medium-severity Missing Authorization vulnerability in the WP-Chatbot for Messenger WordPress plugin, affecting versions <= 4.9. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. No fixed release has been reported yet; treat installations running this software as exposed. Disclosed March 2026, reported by Kazuma Matsumoto.
Vulnerability Overview
The WP-Chatbot for Messenger plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 4.9. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for unauthenticated attackers to overwrite the site's MobileMonkey API token and company ID options, which can be used to hijack chatbot configuration and redirect visitor conversations to an attacker-controlled MobileMonkey account.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.
CWE-862: Missing Authorization
Reaching this weakness in WP-Chatbot for Messenger <= 4.9 takes no account at all. A missing authorization check means a function is reachable by anyone who can reach the endpoint, because the code never asks whether the caller is allowed to perform the action.
Any user who can reach the endpoint gets to run an action reserved for higher-privileged roles, from reading protected data to changing settings or content. No fixed build of this plugin is recorded for WP-Chatbot for Messenger yet, so installs running <= 4.9 stay exposed until the vendor ships one.
Remediation
No known patch available. Please review the vulnerability's details in depth and employ mitigations based on your organization's risk tolerance. It may be best to uninstall the affected software and find a replacement.
How does WordSec protect against this?
This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. No patched version is recorded yet, which is the case where a filtering layer matters most, because there is nothing to update to.
- Login Security
- Alerts
External References
Related records
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