X2Engine 4.2 Arbitrary File Upload

`Vulnerability title: Arbitrary File Upload In X2Engine Inc. X2Engine  
CVE: CVE-2015-5074  
Vendor: X2Engine Inc.  
Product: X2Engine  
Affected version: 4.2  
Fixed version: 5.2  
Reported by: Simone Quatrini  
Details:  
  
It was discovered that authenticated users were able to upload files of any type providing that the file did not have an extension that was listed in the following blacklist:  
  
const EXT_BLACKLIST = '/\.\s*(P<ext>html|htm|js|jsb|mhtml|mht|xhtml|xht|php|phtml|php3|php4|php5|phps|shtml|jhtml|pl|py|cgi|exe|scr|dll|msi|vbs|bat|com|pif|cmd|vxd|cpl|ini|conf|cnf|key|iv|htaccess)\b/i';  
  
However, there is another common (not present in regexp) that allow PHP execution: .PHT. It is therefore possible to execute any PHP code on the remote system.  
  
Further details at:  
  
https://www.portcullis-security.com/security-research-and-downloads/security-advisories/cve-2015-5074/  
  
Copyright:  
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