ModSecurity 3.0.0 Cross Site Scripting

`# Exploit Title: ModSecurity 3.0.0 - Cross-Site Scripting  
# Date: 2018-07-02  
# Vendor Homepage: https://www.modsecurity.org  
# Software: ModSecurity  
# Category: Web Application Firewall  
# Exploit Author: Adipta Basu  
# Tested on: Mac OS High Sierra  
# CVE: N/A  
# Description: ModSecurity 3.0.0 has XSS via an onError attribute of an IMG element  
  
# Details:   
# After doing source code analysis, I found that if <img src=x onError=prompt(111)>   
# is passed as a parameter, a pop-up is obtained. This is because the filter flags   
# terms like "script","alert",etc. Moreover it also flags if there is a string placed  
# inside the first bracket. That is why I had to use 111. However document.cookie when  
# passed works fine.  
  
Reproduction Steps:  
  
- Use <img src=x onError=prompt(3)> or <img src=x onError=prompt(document.cookie)>  
  
`