# CVE-2026-4020: Gravity SMTP <= 2.1.4 - Unauthenticated Sensitive Information Exposure via REST API

> Unauthenticated attackers can access a REST API endpoint to retrieve sensitive system configuration data and API keys from the Gravity SMTP plugin.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 31 Mar 2026
- **Updated:** 8 Apr 2026
- **Also known as:** GHSA-jxfc-8wcq-xxcg

## What is CVE-2026-4020?

CVE-2026-4020 is a high-severity vulnerability in RocketGenius Gravity SMTP, published on 31 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official 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.

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2026-4020?


## How do I fix CVE-2026-4020?

No fix has been published for CVE-2026-4020 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-4020 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-4020 exists.

Public exploit code:

- CVE-2026-4020 - Draft (github_poc): https://github.com/HORKimhab/CVE-2026-4020
- https://github.com/faizdotid/CVE-2026-4020 (github_poc): https://github.com/faizdotid/CVE-2026-4020
- Gravity SMTP WordPress Plugin - Sensitive Information Exposure (nuclei): http/cves/2026/CVE-2026-4020.yaml

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-4020 and fix it if it is affected.

What it is: CVE-2026-4020 is a high-severity vulnerability in RocketGenius Gravity SMTP, published on 31 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-4020 exists.

Affected product: RocketGenius Gravity SMTP. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-4020/ (Markdown: https://insights.sbomify.com/CVE-2026-4020/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-4020
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-4020
- OSV: https://osv.dev/vulnerability/CVE-2026-4020

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-4020/
Summaries are generated and may contain mistakes; the official description above is the record.