
🔐 ⚠️ phpMyAdmin 5.2.3 - 2FA Bypass! 0day++! ⚠️ 🔐
🚨 WebAuthn signatures are parsed but never COSE-verified against credentialPublicKey 🚨 Arbitrary bytes pass the structural checks, so 2FA falls over after password auth 💀
Exploit:
> CWE-347/287 ⚠️ CVSS 8.1
> 🐙
🧩 Root cause: web-auth/webauthn-lib is only a dev/suggest dependency 📦 The distributed tarball is built with `composer install --no-dev`, so `WebAuthn::createServer` instantiates `CustomServer` instead of `WebauthnLibServer` 👀
🔍 How? 🤦♂️ `CustomServer::parseAndValidateAssertionResponse` enforces structural checks only: clientData type, session challenge, origin host, rpIdHash, user-present, allowed credential id 📋 `response.signature` is decoded and never verified ❌ `credentialPublicKey` is never read 🕳️
💥 Impact: a well-formed assertion carrying correct structural fields and an arbitrary signature yields a full authenticated session 🔓 Impact is unauthorized database access through the application, not host-level code execution 🗄️