Description
The Groundhogg — CRM, Newsletters, and Marketing Automation plugin for WordPress is vulnerable to Privilege Escalation via Contact Identity Rebinding in all versions up to, and including, 4.9 The vulnerability exists because the `create_contact` function in the v3 REST endpoint (`POST /gh/v3/contacts`) is gated solely by the `add_contacts` capability and forwards the full request payload — including the security-bearing `user_id` column — into the upsert path of `Contacts_DB::add()`, which bypasses the ownership guard that `Contacts_DB::update()` enforces, allowing an attacker to rebind any existing contact record to an arbitrary WordPress user ID. This makes it possible for authenticated attackers with Sales Representative-level access and above to upsert their own contact row to point to an Administrator's user ID, then invoke the v4 email-test endpoint (`POST /gh/v4/emails/test`) — also accessible to the Sales Representative role via the `send_emails` capability — to generate an `{auto_login_url}` one-time permissions key bound to the rebound contact, and consume that link to call `wp_set_auth_cookie()` and gain a fully authenticated session as the WordPress Administrator.
References9
- plugins.trac.wordpress.org/browser/groundhogg/tags/4.8.3/api/v3…
- plugins.trac.wordpress.org/browser/groundhogg/tags/4.8.3/api/v4…
- plugins.trac.wordpress.org/browser/groundhogg/tags/4.8.3/db/con…
- plugins.trac.wordpress.org/browser/groundhogg/tags/4.8.3/includ…
- plugins.trac.wordpress.org/browser/groundhogg/tags/4.8.3/includ…
- plugins.trac.wordpress.org/browser/groundhogg/tags/4.8.3/includ…
- plugins.trac.wordpress.org/changeset/3724910/groundhogg/trunk/a…
- plugins.trac.wordpress.org/changeset?reponame=&new=3724910%40gr…
- www.wordfence.com/threat-intel/vulnerabilities/id/557306b7-7b66…
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 42 · as of 10 November 2026
- CWE
- CWE-269
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