osTicket 1.12 Formula Injection

`# Exploit Title: osTicket-v1.12 Formula Injection  
# Vendor Homepage: https://osticket.com/  
# Software Link: https://osticket.com/download/  
# Exploit Author: Aishwarya Iyer  
# Contact: https://twitter.com/aish_9524  
# Website: https://about.me/aish_iyer  
# Category: webapps  
# CVE: CVE-2019-14749  
  
1. Description  
  
  
An issue was discovered in osTicket before 1.10.7 and 1.12.x before 1.12.1.  
CSV (aka Formula) injection exists in the export spreadsheets  
functionality. These spreadsheets are generated dynamically from  
unvalidated or unfiltered user input in the Name and Internal Notes fields  
in the Users tab, and the Issue Summary field in the tickets tab. This  
allows other agents to download data in a .csv file format or .xls file  
format. This is used as input for spreadsheet applications such as Excel  
and OpenOffice Calc, resulting in a situation where cells in the  
spreadsheets can contain input from an untrusted source. As a result, the end  
user who is accessing the exported spreadsheet can be affected.  
  
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-14749  
  
2. Proof of Concept  
  
Steps to Reproduce:  
- Login as an agent and under the "Users" section create a new user.  
- Insert the crafted payload of Formula Injection into "Name" and "Internal  
Notes" field.  
- Login as another agent and under the Users tab, click on export and then  
save the ".csv" file.  
- It is observed that the payload gets executed in excel and this leads to  
remote code execution.  
- Not just an agent, even a non-agent user has the option to edit his name  
where he can insert the malicious payload of Formula Injection.  
- The application does not sanitize the inputs here due to which when the  
agent clicks on export the payload gets executed.  
-The same issue persisted in the "Issue Summary" field in the tickets tab.  
  
3. Reference  
  
https://github.com/osTicket/osTicket/commit/99818486c5b1d8aa445cee232825418d6834f249  
https://github.com/osTicket/osTicket/releases/tag/v1.12.1  
https://github.com/osTicket/osTicket/releases/tag/v1.10.7  
  
4. Solution  
  
The vulnerability has been patched by the vendor in the next release which  
is osTicket v1.10.7.  
  
--   
Best Regards,  
Aishwarya Iyer  
https://about.me/aish_iyer  
`