CVE-2026-18436: Mailerpress – Newsletter, Email Marketing & Ai Automation

Medium severity, CVSS 5.3. EPSS: 0.4% chance of exploitation in the next 30 days.

The MailPress plugin for WordPress is vulnerable to unauthorized access in versions up to, and including, 1.5.0 via the campaign revision-restore REST endpoint (POST /wp-json/mailpress/v1/campaign/<id>/restore-revision/<revision_id>). The route in the vulnerable range was registered without a permissionCallback, allowing the restoreRevision() handler to run for unauthenticated requests and overwrite a campaign's content_html with any prior revision. This makes it possible for unauthenticated attackers to modify campaign content by restoring an arbitrary revision.

Affected products

• Mailerpress Mailerpress – Newsletter, Email Marketing & Ai Automation: up to and including 1.5.0

Published 2026-07-31. Last modified 2026-08-12.