Offensive Security Tool: SecretFinder

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Offensive Security Tool: SecretFinder

GitHub Link

Have you ever had secrets for your apps in multiple places? Some are environment variables. Others are in a third party providers like AWS SSM, AWS Secrets Manager, Hashicorp Vault, Google API, Facebook API or any other number of places. Pulling from these locations can be frustrating if you have 2 or 3 in one app for various reasons. SecretFinder provides you a way to have a single unified api to pull from any number of locations.

SecretFinder

SecretFinder written by m4ll0k, is a python script based on LinkFinder, written to discover sensitive data like apikeys, accesstoken, authorizations, jwt,..etc in JavaScript files. It does so by using jsbeautifier for python in combination with a fairly large regular expression. The regular expressions consists of four small regular expressions. These are responsible for finding and search anything on js files.

The output is given in HTML or plaintext.

See Also: Cisco Smart Switches Riddled with Severe Security Holes

Help

usage: SecretFinder.py [-h] [-e] -i INPUT [-o OUTPUT] [-r REGEX] [-b]
                       [-c COOKIE] [-g IGNORE] [-n ONLY] [-H HEADERS]
                       [-p PROXY]

optional arguments:
  -h, --help            show this help message and exit
  -e, --extract         Extract all javascript links located in a page and
                        process it
  -i INPUT, --input INPUT
                        Input a: URL, file or folder
  -o OUTPUT, --output OUTPUT
                        Where to save the file, including file name. Default:
                        output.html
  -r REGEX, --regex REGEX
                        RegEx for filtering purposes against found endpoint
                        (e.g: ^/api/)
  -b, --burp            Support burp exported file
  -c COOKIE, --cookie COOKIE
                        Add cookies for authenticated JS files
  -g IGNORE, --ignore IGNORE
                        Ignore js url, if it contain the provided string
                        (string;string2..)
  -n ONLY, --only ONLY  Process js url, if it contain the provided string
                        (string;string2..)
  -H HEADERS, --headers HEADERS
                        Set headers ("Name:Value\nName:Value")
  -p PROXY, --proxy PROXY
                        Set proxy (host:port)

Installation

SecretFinder supports Python 3.

$ git clone https://github.com/m4ll0k/SecretFinder.git secretfinder
$ cd secretfinder
$ python -m pip install -r requirements.txt or pip install -r requirements.txt
$ python3 SecretFinder.py

See Also: Jeff Moss, aka Dark Tangent, the person who founded DEF CON and Black Hat

Usage

• Most basic usage to find the sensitive data with default regex in an online JavaScript file and output the HTML results to results.html:

python3 SecretFinder.py -i https://example.com/1.js -o results.html

• CLI/STDOUT output (doesn’t use jsbeautifier, which makes it very fast):

python3 SecretFinder.py -i https://example.com/1.js -o cli

• Analyzing an entire domain and its JS files:

python3 SecretFinder.py -i https://example.com/ -e

• Ignore certain js file (like external libs) provided by -g --ignore

python3 SecretFinder.py -i https://example.com/ -e -g 'jquery;bootstrap;api.google.com'

• Process only certain js file provided by -n --only:

python3 SecretFinder.py -i https://example.com/ -e -n 'd3i4yxtzktqr9n.cloudfront.net;www.myexternaljs.com'

• Use your regex:

python3 SecretFinder.py -i https://example.com/1.js -o cli -r 'apikey=my.api.key[a-zA-Z]+'

• Other options: add headers,proxy and cookies:

python3 SecretFinder.py -i https://example.com/ -e -o cli -c 'mysessionid=111234' -H 'x-header:value1\nx-header2:value2' -p 127.0.0.1:8080 -r 'apikey=my.api.key[a-zA-Z]+'

• Input accept all this entries:
• Url: e.g. https://www.google.com/ [-e] is required
• Js url: e.g. https://www.google.com/1.js
• Folder: e.g. myjsfiles/*
• Local file: e.g /js/myjs/file.js

add Regex

• Open SecretFinder.py and add your regex:

_regex = {
    'google_api'     : r'AIza[0-9A-Za-z-_]{35}',
    'google_captcha' : r'6L[0-9A-Za-z-_]{38}|^6[0-9a-zA-Z_-]{39}$',
    'google_oauth'   : r'ya29\.[0-9A-Za-z\-_]+',
    'amazon_aws_access_key_id' : r'AKIA[0-9A-Z]{16}',
    'amazon_mws_auth_toke' : r'amzn\\.mws\\.[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}',
    'amazon_aws_url' : r's3\.amazonaws.com[/]+|[a-zA-Z0-9_-]*\.s3\.amazonaws.com',
    'facebook_access_token' : r'EAACEdEose0cBA[0-9A-Za-z]+',
    'authorization_basic' : r'basic\s*[a-zA-Z0-9=:_\+\/-]+',
    'authorization_bearer' : r'bearer\s*[a-zA-Z0-9_\-\.=:_\+\/]+',
    'authorization_api' : r'api[key|\s*]+[a-zA-Z0-9_\-]+',
    'mailgun_api_key' : r'key-[0-9a-zA-Z]{32}',
    'twilio_api_key' : r'SK[0-9a-fA-F]{32}',
    'twilio_account_sid' : r'AC[a-zA-Z0-9_\-]{32}',
    'twilio_app_sid' : r'AP[a-zA-Z0-9_\-]{32}',
    'paypal_braintree_access_token' : r'access_token\$production\$[0-9a-z]{16}\$[0-9a-f]{32}',
    'square_oauth_secret' : r'sq0csp-[ 0-9A-Za-z\-_]{43}|sq0[a-z]{3}-[0-9A-Za-z\-_]{22,43}',
    'square_access_token' : r'sqOatp-[0-9A-Za-z\-_]{22}|EAAA[a-zA-Z0-9]{60}',
    'stripe_standard_api' : r'sk_live_[0-9a-zA-Z]{24}',
    'stripe_restricted_api' : r'rk_live_[0-9a-zA-Z]{24}',
    'github_access_token' : r'[a-zA-Z0-9_-]*:[a-zA-Z0-9_\-]+@github\.com*',
    'rsa_private_key' : r'-----BEGIN RSA PRIVATE KEY-----',
    'ssh_dsa_private_key' : r'-----BEGIN DSA PRIVATE KEY-----',
    'ssh_dc_private_key' : r'-----BEGIN EC PRIVATE KEY-----',
    'pgp_private_block' : r'-----BEGIN PGP PRIVATE KEY BLOCK-----',
    'json_web_token' : r'ey[A-Za-z0-9-_=]+\.[A-Za-z0-9-_=]+\.?[A-Za-z0-9-_.+/=]*$',
    
    'name_for_my_regex' : r'my_regex', 
    # for example
    'example_api_key'    : r'^example\w+{10,50}'
}

See Also: Offensive Security Tool: CloudFail