---
id: "CVE-2026-121450"
kind: "vulnerability"
aliases: ["CVE-2026-121450"]
title: "CFNext: subscription UUID leaks admin password through weak MD5 derivation"
severity: "high"
cvss: 7.7
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["cfnext", "cloudflare-workers", "package", "self-hosted"]
not_affected_if: ["version-3.1.0-or-later"]
published_at: "2026-11-03T16:17:23+00:00"
first_seen_at: "2026-11-03T16:21:43+00:00"
updated_at: "2026-11-03T16:23:50+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-121450", "first_seen_at": "2026-11-03T16:21:43+00:00"}]
---

# CFNext: subscription UUID leaks admin password through weak MD5 derivation

CFNext before 3.1.0 derives each subscription UUID as an MD5 of the admin password using a fixed public salt. Anyone holding a subscription link can brute-force the password offline without rate limits, then log into the admin panel and read stored Trojan, Clash, Telegram and Cloudflare API secrets.

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

## How to check

- Check the CFNext version in the deployed project; versions below `3.1.0` are in scope.
- Look for a subscription link that contains a UUID; if the UUID is an MD5 of the admin password, the derivation is in use.

## Fix

- Move to `3.1.0` or later.

## Timeline

- 2026-11-03T16:21:43+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-121450

## Documents

- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/cfnext-before-3.1.0-admin-password-recovery-via-md5-derived-subscription-uuid
- [fix] Patch: github.com https://github.com/PAICNI/CFNext/commit/ca8ad82bb7c635f765c82a1cd0c954fd70d81fb7

## From the sources

CFNext before 3.1.0 contains a weak cryptographic derivation vulnerability that allows subscription link holders to recover the admin password because the subscription UUID is an MD5 of the password with a fixed public salt. Attackers can brute-force the password offline without rate limiting, log into the admin panel, and read stored Trojan, Clash, Telegram and Cloudflare API secrets.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_