CVE-2026-78003

Critical

Description

The Mailgun for WordPress plugin for WordPress is vulnerable to Server-Side Request Forgery (SSRF) via path traversal in versions up to and including 2.2.0. This is due to insufficient input validation in the add_list() function, which accepts user-controlled array keys from $_POST['addresses'], passes them through sanitize_text_field(). This makes it possible for unauthenticated attackers to make authenticated POST requests to any Mailgun API endpoint using the WordPress site's API key, including creating inbound email-forwarding routes that can intercept password reset emails, leading to administrator account takeover.

SeverityCritical
CVSS9.8
Exploit probability—
ProductMailgun for WordPress
PublishedAug 22, 2026
First seenAug 22, 2026

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
mailgun Mailgun for WordPressv ≤ 2.2.0—

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CVE-2026-78003 · Mailgun for WordPress · Dark Radar