Offensive Security Tool: Nginxpwner

Reading Time: 2 Minutes

Description

Nginxpwner is written by stark0de and its an automated tool written in Python that can be used to scan a web server running the nginx web server software for misconfigurations and vulnerabilities. The tool uses a variety of techniques to identify misconfigurations and vulnerabilities, such as looking for files with default or weak permissions, searching for backup files, and checking for common server configuration mistakes. Once the tool identifies a vulnerability, it attempts to exploit it by running a variety of pre-configured attacks against the server, such as using a local file inclusion (LFI) vulnerability to retrieve sensitive files or attempting to execute arbitrary code on the server.

It can also be used to perform reconnaissance on a target server, such as identifying the operating system and web server software in use. It is important to note that while the tool can be useful for identifying potential security issues on a web server, it should only be used on systems that you have explicit permission to test.

Install

cd /opt

git clone https://github.com/stark0de/nginxpwner

cd nginxpwner

chmod +x install.sh

./install.sh

Install using Docker

git clone https://github.com/stark0de/nginxpwner

cd nginxpwner

sudo docker build -t nginxpwner:latest .

Run the image

sudo docker run -it nginxpwner:latest /bin/bash

Usage

Target tab in Burp, select host, right click, copy all URLs in this host, copy to a file

cat urllist | unfurl paths | cut -d"/" -f2-3 | sort -u > /tmp/pathlist 

Or get the list of paths you already discovered in the application in some other way. Note: the paths should not start with /

Finally:

python3 nginxpwner.py https://example.com /tmp/pathlist

Notes

It actually checks for:

-Gets Ngnix version and gets its possible exploits using searchsploit and tells if it is outdated

-Throws a wordlist specific to Nginx via gobuster

-Checks if it is vulnerable to CRLF via a common misconfiguration of using $uri in redirects

-Checks for CRLF in all of the paths provided

-Checks if the PURGE HTTP method is available from the outside

-Checks for variable leakage misconfiguration

-Checks for path traversal vulnerabilities via merge_slashes set to off

-Tests for differences in the length of responses when using hop-by-hop headers (ex: X-Forwarded-Host)

-Uses Kyubi to test for path traversal vulnerabilities via misconfigured alias

-Tests for 401/403 bypass using X-Accel-Redirect

-Shows the payload to check for Raw backend reading response misconfiguration

-Checks if the site uses PHP and suggests some nginx-specific tests for PHP sites

-Tests for the common integer overflow vulnerability in Nginx’s range filter module (CVE-2017-7529)

The tool uses the Server header in the response to do some of the tests. There are other CMS and so which are built on Nginx like Centminmod, OpenResty, Pantheon or Tengine for example which don’t return that header. In that case please use nginx-pwner-no-server-header.py with the same parameters than the other script

Also, for the exploit search to run correctly you should do: searchsploit -u in Kali from time to time

The tool does not check for web cache poisoning/deception vulnerabilities nor request smuggling, you should test that with specific tools for those vulnerabilities. NginxPwner is mainly focused in misconfigurations developers may have introduced in the nginx.conf without being aware of them.

Clone the repo from here: GitHub Link