WP Mail Gateway <= 1.8 - Missing Authorization to Authenticated (Subscriber+) SMTP Configuration Modification via 'wmg_save_provider_config' AJAX Action
Strategic Overview
- Status
- Patched in 1.8.1
- Affected Plugin
- WP Mail Gateway
- Affected Version
<= 1.8- CVSS
- 8.8High
- Weakness type
- CWE-862 · Missing Authorization
- CVE
CVE-2026-6963
At a glance
CVE-2026-6963 is a high-severity Missing Authorization vulnerability in the WP Mail Gateway WordPress plugin, affecting versions <= 1.8. It carries a CVSS score of 8.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires an authenticated account at Subscriber level or above. The issue is fixed in version 1.8.1; sites on affected versions should update now. Disclosed May 2026, reported by Nabil Irawan.
Vulnerability Overview
The WP Mail Gateway plugin for WordPress is vulnerable to unauthorized access due to a missing capability check on the wmg_save_provider_config AJAX action in all versions up to, and including, 1.8. This makes it possible for authenticated attackers, with Subscriber-level access and above, to update SMTP settings and redirect mail which can be used for privilege escalation by triggering a password reset email and using that to access and administrator's 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 interaction from a victim user. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.
CWE-862: Missing Authorization
Reaching this weakness in WP Mail Gateway <= 1.8 takes an account at Subscriber level or above. 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 WP Mail Gateway the fix is 1.8.1: builds <= 1.8 are affected, anything from 1.8.1 onward is not.
Remediation
Update to version 1.8.1, or a newer patched version
How does WordSec protect against this?
Because it turns on account access, WordSec's login security is the relevant layer: role-based two-factor, captcha and brute-force limits raise the cost of getting the account this needs. None of that substitutes for the fix: WP Mail Gateway 1.8.1 closes this, and updating the plugin is the step that ends it.
- Login Security
- Alerts
External References
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