---
title: "CVE-2026-105857: Payload Form Builder has an RCE issue"
url: https://erroneo.us/security/cve/CVE-2026-105857/
description: "CVE-2026-105857 (@payloadcms/plugin-form-builder (npm)): Payload is a free and open source headless content management system. In…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-10-06
date_modified: 2026-10-07
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-105857"
kev: false
cvss: 10
epss: 0.00434
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-105857: Payload Form Builder has an RCE issue

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.4% , percentile 37: FIRST’s model estimates a 0.4% chance of exploitation activity in the next 30 days, higher than 37% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes @payloadcms/plugin-form-builder (npm) < 3.90.0, fixed in 3.90.0 ; @payloadcms/plugin-form-builder (npm) >= 4.0.0-canary.0, < 4.0.0-canary.34, fixed in 4.0.0-canary.34 . Check your lockfile, including transitive dependencies.

## What it is

Payload is a free and open source headless content management system. In @payloadcms/plugin-form-builder versions before 3.90.0 and canary versions before 4.0.0-canary.34, an attacker can craft a form submission that executes code remotely on the server. This issue is fixed in versions 3.90.0 and 4.0.0-canary.34.

## Affected packages

- npm `@payloadcms/plugin-form-builder` < 3.90.0 → fixed: 3.90.0
- npm `@payloadcms/plugin-form-builder` >= 4.0.0-canary.0, < 4.0.0-canary.34 → fixed: 4.0.0-canary.34

## Affected products (CVE record)

- payloadcms payload: < 3.90.0, >= 4.0.0-canary.0, < 4.0.0-canary.34

## Severity

- GitHub_M CVSS 3.1: 10 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`
- GitHub CVSS 3.1: 10.0 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.43% probability of exploitation activity in the next 30 days; percentile 37.

## Sources

- [GitHub Advisory GHSA-r488-j9vj-wx3q](https://github.com/advisories/GHSA-r488-j9vj-wx3q)
- [CVE.org record CVE-2026-105857](https://www.cve.org/CVERecord?id=CVE-2026-105857)
- [NVD entry CVE-2026-105857](https://nvd.nist.gov/vuln/detail/CVE-2026-105857)
- [github.com](https://github.com/payloadcms/payload/security/advisories/GHSA-r488-j9vj-wx3q)
- [github.com](https://github.com/payloadcms/payload/commit/333b82b9f3e685fed6826c2e3270da79df8336c6)
- [github.com](https://github.com/payloadcms/payload/releases/tag/v3.90.0)

---
Source page: https://erroneo.us/security/cve/CVE-2026-105857/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt