---
id: "CVE-2026-119561"
kind: "vulnerability"
aliases: ["CVE-2026-119561"]
title: "phpMyAdmin: WebAuthn check skips signature verification, letting attackers bypass second factor"
severity: "high"
cvss: 7.6
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["mysql", "package", "php", "phpmyadmin", "webauthn"]
not_affected_if: ["newer-version", "no-webauthn-2fa"]
published_at: "2026-10-30T12:16:43+00:00"
first_seen_at: "2026-10-30T12:30:26+00:00"
updated_at: "2026-10-30T12:32:19+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-119561", "first_seen_at": "2026-10-30T12:30:26+00:00"}]
---

# phpMyAdmin: WebAuthn check skips signature verification, letting attackers bypass second factor

phpMyAdmin through 5.2.3 does not check WebAuthn assertion signatures against stored public keys during login. An attacker who already holds a victim's MySQL credentials can submit a crafted response to skip the second factor and gain database privileges.

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

## How to check

- Check the installed phpMyAdmin version and whether it is `5.2.3` or earlier.
- Check whether WebAuthn or security-key two-factor login is enabled in the phpMyAdmin configuration.

## Fix

- Move to a phpMyAdmin release later than `5.2.3`; the sources do not name the fixed version.

## Timeline

- 2026-10-30T12:30:26+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-119561

## From the sources

phpMyAdmin through 5.2.3 contains an authentication bypass vulnerability in CustomServer::parseAndValidateAssertionResponse() that never verifies WebAuthn assertion signatures against stored public keys. Attackers holding a victim's MySQL credentials can POST a crafted webauthn_request_response with matching challenge, origin, and rpIdHash to bypass the second factor and gain database privileges.

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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_