---
title: "CVE-2026-105863: Payload authentication token field handling issue"
url: https://erroneo.us/security/cve/CVE-2026-105863/
description: "CVE-2026-105863 (payload (npm)): Payload is a free and open source headless content management system. In versions after 3.0.0 and before 3.90.0, a custom…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-10-06
date_modified: 2026-10-09
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-105863"
kev: false
cvss: 9.2
epss: 0.00376
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-105863: Payload authentication token field handling 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 30: FIRST’s model estimates a 0.4% chance of exploitation activity in the next 30 days, higher than 30% 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 payload (npm) >= 3.0.0, < 3.90.0, fixed in 3.90.0 ; payload (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 versions after 3.0.0 and before 3.90.0, a custom field option that maps a field to a reserved authentication claim name can place unintended values in the authentication token issued at login. This issue is fixed in version 3.90.0.

## Affected packages

- npm `payload` >= 3.0.0, < 3.90.0 → fixed: 3.90.0
- npm `payload` >= 4.0.0-canary.0, < 4.0.0-canary.34 → fixed: 4.0.0-canary.34

## Affected products (CVE record)

- payloadcms payload: >= 3.0.0, < 3.90.0, >= 4.0.0-canary.0, < 4.0.0-canary.34

## Severity

- GitHub_M CVSS 4.0: 9.2 `CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`
- GitHub CVSS 4.0: 9.2 `CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`

## 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): 0.38% probability of exploitation activity in the next 30 days; percentile 30.

## Sources

- [GitHub Advisory GHSA-66wr-7vmr-p5jq](https://github.com/advisories/GHSA-66wr-7vmr-p5jq)
- [CVE.org record CVE-2026-105863](https://www.cve.org/CVERecord?id=CVE-2026-105863)
- [NVD entry CVE-2026-105863](https://nvd.nist.gov/vuln/detail/CVE-2026-105863)
- [github.com](https://github.com/payloadcms/payload/security/advisories/GHSA-66wr-7vmr-p5jq)
- [github.com](https://github.com/payloadcms/payload/commit/56cd5cd050a57daebf33159e41e5ff9d4a45239c)
- [github.com](https://github.com/payloadcms/payload/releases/tag/v3.90.0)

---
Source page: https://erroneo.us/security/cve/CVE-2026-105863/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt