# CVE-2026-84434: Gravity Forms <= 3.1.0.4 - Unauthenticated Arbitrary File Upload via Hidden File Upload Field

> Unauthenticated attackers can upload executable files via hidden fields in Gravity Forms, leading to remote code execution.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 19 Sep 2026
- **Updated:** 19 Sep 2026
- **Also known as:** GHSA-x9x4-5g6j-pvj3

## What is CVE-2026-84434?

CVE-2026-84434 is a critical vulnerability in Gravity Forms, published on 19 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Gravity Forms plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 3.1.0.4 via the upload_file function. This is due to a mismatch between the field validation pipeline and the file persistence pipeline, where hidden file upload fields bypass extension validation and a rejected file's intact upload state is later passed to upload_file() without re-validation. This makes it possible for unauthenticated attackers to upload files that may be executable, which makes remote code execution possible. Exploitation requires the targeted form to contain a File Upload field with its Visibility set to 'Hidden'; the vulnerability is reachable by unauthenticated attackers on any publicly accessible form meeting this condition.

Weakness: CWE-434 (Unrestricted Upload of File with Dangerous Type)

## Which versions are affected by CVE-2026-84434?


## How do I fix CVE-2026-84434?

No fix has been published for CVE-2026-84434 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-84434 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-84434 exists.

Public exploit code:

- PoC for CVE-2026-84434: unauthenticated arbitrary file upload in Gravity Forms ≤3.1.0.4 via hidden File Upload fields. Python check/exploit/mass scan. (github_poc): https://github.com/murrez/CVE-2026-84434
- WordPress Gravity Forms Plugin <=3.1.0.4 - Unauthenticated Arbitrary File Upload (nuclei): http/cves/2026/CVE-2026-84434.yaml

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-84434 and fix it if it is affected.

What it is: CVE-2026-84434 is a critical vulnerability in Gravity Forms, published on 19 Sep 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-2026-84434 exists.

Affected product: Gravity Forms. 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-2026-84434/ (Markdown: https://insights.sbomify.com/CVE-2026-84434/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-84434
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-84434
- OSV: https://osv.dev/vulnerability/CVE-2026-84434

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-84434/
Summaries are generated and may contain mistakes; the official description above is the record.