Sendmachine for WordPress <= 1.0.20 - Unauthenticated SMTP Hijack to Privilege Escalation via manage_admin_requests
Strategic Overview
- Status
- Patched in 2.0.0
- Affected Plugin
- Sendmachine for WordPress
- Affected Version
<= 1.0.20- CVSS
- 9.8Critical
- Weakness type
- CWE-862 · Missing Authorization
- CVE
CVE-2026-6235
At a glance
CVE-2026-6235 is a critical-severity Missing Authorization vulnerability in the Sendmachine for WordPress WordPress plugin, affecting versions <= 1.0.20. It carries a CVSS score of 9.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 2.0.0; sites on affected versions should update now. Disclosed April 2026, reported by Nabil Irawan.
Vulnerability Overview
The Sendmachine for WordPress plugin for WordPress is vulnerable to authorization bypass via the 'manage_admin_requests' function in all versions up to, and including, 1.0.20. 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 plugin's SMTP configuration, which can be leveraged to intercept all outbound emails from the site (including password reset emails).
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. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.
CWE-862: Missing Authorization
Sendmachine for WordPress <= 1.0.20 carries this weakness at manage_admin_requests, and reaching it 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. For Sendmachine for WordPress the fix is 2.0.0: builds <= 1.0.20 are affected, anything from 2.0.0 onward is not.
Remediation
Update to version 2.0.0, or a newer patched version
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. None of that substitutes for the fix: Sendmachine for WordPress 2.0.0 closes this, and updating the plugin is the step that ends it.
- Login Security
- Alerts
External References
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