log4j.scan

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

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.

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Description

We have been researching the Log4J RCE (CVE-2021-44228) since it was released, and we worked in preventing this vulnerability with our customers. We 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 set up a DNS callback server.

Usage

$ python3 log4j.py -h
python3 log4j.py -h
[•] CVE-2021-44228 - Apache Log4j RCE Scanner
[•] Scanner provided by log4j.github.io - The Next-Gen Attack Surface Management Platform.
[•] Secure your External Attack Surface with log4j.github.io
usage: log4j.py [-h] [-u URL] [-p PROXY] [-l USEDLIST] [--request-type REQUEST_TYPE] [--headers-file HEADERS_FILE] [--run-all-tests] [--exclude-user-agent-fuzzing]
                     [--wait-time WAIT_TIME] [--waf-bypass] [--custom-waf-bypass-payload CUSTOM_WAF_BYPASS_PAYLOAD] [--test-CVE-2021-45046] [--test-CVE-2022-42889]
                     [--dns-callback-provider DNS_CALLBACK_PROVIDER] [--custom-dns-callback-host CUSTOM_DNS_CALLBACK_HOST] [--disable-http-redirects]

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.
  --custom-waf-bypass-payload CUSTOM_WAF_BYPASS_PAYLOAD
                        Test with custom WAF bypass payload.
  --test-CVE-2021-45046
                        Test using payloads for CVE-2021-45046 (detection payloads).
  --test-CVE-2022-42889
                        Test using payloads for Apache Commons Text RCE (CVE-2022-42889).
  --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.
  --disable-http-redirects
                        Disable HTTP redirects. Note: HTTP redirects are useful as it allows the payloads to have a higher chance of reaching vulnerable systems.