Groundhogg — CRM, Newsletters, and Marketing Automation <= 4.5.2 - Insecure Direct Object Reference

Summary

The Groundhogg — CRM, Newsletters, and Marketing Automation plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 4.5.2 via the GET /wp-json/gh/v4/contacts/<id> REST endpoint. The endpoint's permission callback checks only the role-level view_contacts capability and read_single() returns the full contact record by sequential integer ID without the object-level view_contact ownership check applied elsewhere in the codebase. This makes it possible for authenticated attackers holding view_contacts but not view_others_contacts — notably Groundhogg's built-in Sales Rep role, designed to see only its own contacts — to read any contact record on the site, including PII, contact meta, owner IDs, the admin edit URL, and (for contacts linked to a WordPress user) that user's full capability set.

Timeline

1. Aug 5, 2026, 6:37 AM UTCCVE published
2. Aug 5, 2026, 1:30 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. Aug 5, 2026, 1:30 PM UTCRecord last updated

Affected versions

• trainingbusinesspros Groundhogg — CRM, Newsletters, and Marketing Automation

  through 4.5.2

References 9