Description
The Gravity SMTP plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 2.1.4. This is due to a REST API endpoint registered at /wp-json/gravitysmtp/v1/tests/mock-data with a permission_callback that unconditionally returns true, allowing any unauthenticated visitor to access it. When the ?page=gravitysmtp-settings query parameter is appended, the plugin's register_connector_data() method populates internal connector data, causing the endpoint to return approximately 365 KB of JSON containing the full System Report. This makes it possible for unauthenticated attackers to retrieve detailed system configuration data including PHP version, loaded extensions, web server version, document root path, database server type and version, WordPress version, all active plugins with versions, active theme, WordPress configuration details, database table names, and any API keys/tokens configured in the plugin.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| RocketGenius | Gravity SMTP | ≤ 2.1.4 | — |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
GitHub 2 repositories
-
faizdotid/CVE-2026-4020 ★ 0 · Jun 30, 2026
-
HORKimhab/CVE-2026-4020 ★ 0 · Jun 22, 2026
CVE-2026-4020 - Draft
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Automated scanner template
A ready-made Nuclei template detects this vulnerability automatically. Vulnerabilities with public scanner templates are typically probed across the internet soon after the template appears — exposed systems should be patched first.
- Gravity SMTP WordPress Plugin - Sensitive Information Exposure http/cves/2026/CVE-2026-4020.yaml
Source: projectdiscovery/nuclei-templates (MIT) — updated daily. Only links are listed.
References
- https://www.wordfence.com/threat-intel/vulnerabilities/id/12a296db-ecc0-409b-8718-0c208504053a?source=cve
- https://www.gravityforms.com/gravity-smtp/
- https://plugins.trac.wordpress.org/browser/gravitysmtp/trunk/vendor/gravityforms/gravity-tools/src/Providers/class-config-collection-service-provider.php#L86
- https://plugins.trac.wordpress.org/browser/gravitysmtp/tags/2.1.4/vendor/gravityforms/gravity-tools/src/Providers/class-config-collection-service-provider.php#L86
- https://plugins.trac.wordpress.org/browser/gravitysmtp/trunk/vendor/gravityforms/gravity-tools/src/Providers/class-config-collection-service-provider.php#L103
- https://plugins.trac.wordpress.org/browser/gravitysmtp/tags/2.1.4/vendor/gravityforms/gravity-tools/src/Providers/class-config-collection-service-provider.php#L103
- https://docs.gravitysmtp.com/gravity-smtp-changelog/