# CVE-2026-81278: WPExperts Post SMTP missing authorization in settings management

Source: https://junglewise.ai/threats/cve-2026-81278-wpexperts-post-smtp-missing-authorization-in-settings-management  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-31. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-81278 · Severity: medium · CVSS 5.4 · Published 2026-08-31

Post SMTP is a WordPress plugin for email delivery and SMTP configuration. A missing authorization vulnerability allows users with low-level subscriber privileges to change critical site settings including security configurations, potentially disabling security features or locking out administrators.

Vendors: [WPExperts](https://junglewise.ai/threats/vendors/wpexperts).

## Quick answers

**Is CVE-2026-81278 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-81278 being exploited in the wild.

**How severe is CVE-2026-81278?** Medium severity, with a CVSS score of 5.4, published 31 August 2026.

**Which products and versions are affected?** WPExperts Post SMTP 4.0.0 through beta.1.

**Is there a fix for CVE-2026-81278?** A patch was published on 2026-08-26: Fixed in version 4.0.1 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-81278 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-81278?** Check whether you run WPExperts Post SMTP at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a broken access control issue (OWASP A1) in Post SMTP versions 4.0.0 through beta.1. The plugin fails to properly validate user permissions before allowing settings changes, permitting a subscriber-level authenticated user to modify sensitive plugin and site configurations. The attack requires a valid WordPress user account with subscriber or higher privileges. An attacker can alter email settings, disable security features, or modify plugin behavior without proper authorization checks. The issue has been patched in version 4.0.1.

## Affected products

- WPExperts Post SMTP 4.0.0 through beta.1

## Timeline

- 2026-08-24: disclosed: Reported by mad4cyber
- 2026-08-26: advisory: Published by Patchstack
- 2026-08-26: patched: Fixed in version 4.0.1

## References

- [https://wordpress.org/plugins](https://wordpress.org/plugins)
- [https://patchstack.com/database/wordpress/plugin/post-smtp/vulnerability/wordpress-post-smtp-plugin-4-0-0-beta-1-settings-change-vulnerability?_s_id=cve](https://patchstack.com/database/wordpress/plugin/post-smtp/vulnerability/wordpress-post-smtp-plugin-4-0-0-beta-1-settings-change-vulnerability?_s_id=cve)

## Related threats

- [WPExperts Post SMTP unauthenticated XSS](https://junglewise.ai/threats/cve-2026-48838-wpexperts-post-smtp-unauthenticated-xss)