---
id: "CVE-2026-124432"
page: "https://infrastack.ai/live/CVE-2026-124432"
kind: "vulnerability"
aliases: ["CVE-2026-124432"]
title: "phpMyFAQ: passkey login endpoint lets attackers enumerate existing accounts"
severity: "high"
cvss: 7.3
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["package", "php", "phpmyfaq", "self-hosted"]
not_affected_if: ["no-passkeys", "unaffected-version"]
published_at: "2026-11-08T14:18:09+00:00"
first_seen_at: "2026-11-08T14:48:38+00:00"
updated_at: "2026-11-08T14:49:22+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-124432", "first_seen_at": "2026-11-08T14:48:38+00:00"}]
exploit_sources: []
---

# phpMyFAQ: passkey login endpoint lets attackers enumerate existing accounts

Link for people: https://infrastack.ai/live/CVE-2026-124432 (this .md is for agents)

phpMyFAQ's unauthenticated passkey login endpoint returns stable credential IDs for accounts that have passkeys but a time-based fallback ID for others. An attacker can compare responses to learn which accounts exist and obtain their credential IDs.

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

## How to check

- Check the installed phpMyFAQ version: `4.1.9` or `4.2.0` pre-release builds before `4.2.0-beta.3` are affected.
- Look for the passkey endpoint `POST /api/webauthn/prepare-login` on the public site.

## Fix

- phpMyFAQ 4.1.x: move to `4.1.11` or later
- phpMyFAQ 4.2.0 pre-releases: move to `4.2.0-beta.3` or later

## Timeline

- 2026-11-08T14:48:38+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-124432

## Documents

- [advisory] Vendor advisory: github.com https://github.com/thorsten/phpMyFAQ/security/advisories/GHSA-2rvx-pqfw-q35r
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/phpmyfaq-before-4.1.11-and-4.2.0-beta.3-account-enumeration-via-webauthn-prepare-login

## From the sources

phpMyFAQ 4.1.9 before 4.1.11 and 4.2.0 pre-releases before 4.2.0-beta.3 contain an account enumeration vulnerability in the unauthenticated POST /api/webauthn/prepare-login endpoint, which returns stable stored credential IDs for passkey-registered accounts but an md5(time())-derived fallback ID otherwise. Unauthenticated attackers can compare allowCredentials IDs from requests sent more than one second apart, without rate limiting, to identify existing passkey-registered accounts and their credential IDs.

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