Offensive Security Tool: log4j-scan

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Offensive Security Tool: log4j-scan

GitHub Link

log4j-scan

A fully automated, accurate, and extensive scanner for finding vulnerable log4j hosts.

Description

This tool written by fullhunt, who have been researching the Log4J RCE (CVE-2021-44228) since it was released, and worked in preventing this vulnerability with their customers. They are open-sourcing an open detection and scanning tool for discovering and fuzzing for Log4J RCE CVE-2021-44228 vulnerability. This shall be used by security teams to scan their infrastructure for Log4J RCE, and also test for WAF bypasses that can result in achieving code execution on the organization’s environment.

It supports DNS OOB callbacks out of the box, there is no need to setup a DNS callback server.

See Also: Log4j attackers switch to injecting Monero miners via RMI

Features

• Support for lists of URLs.
• Fuzzing for more than 60 HTTP request headers (not only 3-4 headers as previously seen tools).
• Fuzzing for HTTP POST Data parameters.
• Fuzzing for JSON data parameters.
• Supports DNS callback for vulnerability discovery and validation.
• WAF Bypass payloads.

Usage

$ python3 log4j-scan.py -h
[•] CVE-2021-44228 - Apache Log4j RCE Scanner
[•] Scanner provided by FullHunt.io - The Next-Gen Attack Surface Management Platform.
[•] Secure your External Attack Surface with FullHunt.io.
usage: log4j-scan.py [-h] [-u URL] [-l USEDLIST] [--request-type REQUEST_TYPE] [--headers-file HEADERS_FILE] [--run-all-tests] [--exclude-user-agent-fuzzing]
                     [--wait-time WAIT_TIME] [--waf-bypass] [--dns-callback-provider DNS_CALLBACK_PROVIDER] [--custom-dns-callback-host CUSTOM_DNS_CALLBACK_HOST]

optional arguments:
  -h, --help            show this help message and exit
  -u URL, --url URL     Check a single URL.
  -p PROXY, --proxy PROXY
                        Send requests through proxy.
  -l USEDLIST, --list USEDLIST
                        Check a list of URLs.
  --request-type REQUEST_TYPE
                        Request Type: (get, post) - [Default: get].
  --headers-file HEADERS_FILE
                        Headers fuzzing list - [default: headers.txt].
  --run-all-tests       Run all available tests on each URL.
  --exclude-user-agent-fuzzing
                        Exclude User-Agent header from fuzzing - useful to bypass weak checks on User-Agents.
  --wait-time WAIT_TIME
                        Wait time after all URLs are processed (in seconds) - [Default: 5].
  --waf-bypass          Extend scans with WAF bypass payloads.
  --dns-callback-provider DNS_CALLBACK_PROVIDER
                        DNS Callback provider (Options: dnslog.cn, interact.sh) - [Default: interact.sh].
  --custom-dns-callback-host CUSTOM_DNS_CALLBACK_HOST
                        Custom DNS Callback Host.

See Also: Complete Offensive Security and Ethical Hacking Course

Scan a Single URL

$ python3 log4j-scan.py -u https://log4j.lab.secbot.local

Scan a Single URL using all Request Methods: GET, POST (url-encoded form), POST (JSON body)

$ python3 log4j-scan.py -u https://log4j.lab.secbot.local –run-all-tests

Discover WAF bypasses on the environment.

$ python3 log4j-scan.py -u https://log4j.lab.secbot.local –waf-bypass

Scan a list of URLs

$ python3 log4j-scan.py -l urls.txt

Installation

$ pip3 install -r requirements.txt

Docker Support

git clone https://github.com/fullhunt/log4j-scan.git
cd log4j-scan
sudo docker build -t log4j-scan .
sudo docker run -it --rm log4j-scan

# With URL list "urls.txt" in current directory
docker run -it --rm -v $PWD:/data log4j-scan -l /data/urls.txt

Legal Disclaimer

This project is made for educational and ethical testing purposes only. Usage of log4j-scan for attacking targets without prior mutual consent is illegal. It is the end user’s responsibility to obey all applicable local, state and federal laws.

See Also: Hacking stories – Rafael Núñez (aka RaFa), hacking NASA with the hacking group: World of Hell