---
id: "CVE-2026-126937"
page: "https://infrastack.ai/live/CVE-2026-126937"
kind: "vulnerability"
aliases: ["CVE-2026-126937"]
title: "Zipline: setup race lets unauthenticated attackers create superadmin accounts"
severity: "critical"
cvss: 9.2
epss: null
exploited: false
status: "open"
category: "package"
products: [{"name": "Zipline", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["docker", "package", "self-hosted", "zipline"]
not_affected_if: ["fixed-version", "setup-completed"]
published_at: "2026-11-13T10:18:00+00:00"
first_seen_at: "2026-11-13T10:47:27+00:00"
updated_at: "2026-11-13T10:48:33+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-126937", "first_seen_at": "2026-11-13T10:47:27+00:00"}]
exploit_sources: []
---

# Zipline: setup race lets unauthenticated attackers create superadmin accounts

Link for people: https://infrastack.ai/live/CVE-2026-126937 (this .md is for agents)

Zipline before 4.6.5 has a race condition in its POST /api/setup endpoint that lets unauthenticated attackers create multiple SUPERADMIN accounts by sending concurrent requests before the first-setup flag resets. A successful attacker gains full administrative control of the Zipline instance.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Zipline affected range not listed fixed no fixed version listed

## How to check

- Check the Zipline version running on the instance; versions before `4.6.5` are in the stated range.
- Look for unexpected SUPERADMIN accounts in the user list of the Zipline instance.
- Check whether the instance's `/api/setup` endpoint is reachable from the internet.

## Fix

- Zipline: move to `4.6.5` or later.

## Timeline

- 2026-11-13T10:47:27+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-126937

## Documents

- [advisory] Vendor advisory: github.com https://github.com/diced/zipline/security/advisories/GHSA-wgjv-p9mm-qw77
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/zipline-before-4.6.5-toctou-race-condition-via-api-setup

## From the sources

Zipline before 4.6.5 contains a TOCTOU race condition in the POST /api/setup endpoint that allows unauthenticated attackers to create multiple SUPERADMIN accounts by racing concurrent requests before the firstSetup flag is reset. Attackers can send simultaneous requests with spoofed X-Forwarded-For headers during the argon2 hashing window to gain full administrative control of the instance.

---

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