Waf bypass cheat sheet

By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service. Information Security Stack Exchange is a question and answer site for information security professionals. It only takes a minute to sign up. I have been trying to find sql injection against a site in bug bounty.

I tried a few parameters via sql map. One such query was shown to be injectible. The waf used by the website is KONA akmai. Sqlmap could not retrieve any data. NOTE:-whenever i inject it. It gives back a error generated by waf. There is a potential for automated tools to provide false positives in case of blind SQL injection even if there is a slight difference in responses.

This may also be the case where WAF's are involved. I would normally consider that anyone putting their site up for a bug bounty program have done their homework and secured their site reasonably to make it resilient to automated tools. If you get even a slight indication that the site may be vulnerable through automated tools, this must be followed by manual investigation to see if the site is actually vulnerable and what will be the impact if the vulnerability can be exploited.

Also, be wary of extracting data from the database once you know the SQL injection is exploitable and may result in data extraction. If the website stored sensitive information, the site owner might not want you to exploit the vulnerability to extract any potentially sensitive data. Sign up to join this community.

The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. Asked 1 year, 2 months ago. Active 1 month ago. Viewed 1k times. Is it a false positive? If it isnt should i not automate it and try and probe manually?We recently migrated our community to a new web platform and regretably the content for this page needed to be programmatically ported from its previous wiki page.

SQL injection attacks are a type of injection attackin which SQL commands are injected into data-plane input in order to effect the execution of predefined SQL commands. The given example works in case of cleaning of dangerous traffic, not in case of blocking the entire request or the attack source.

waf bypass cheat sheet

Example Number 2 of a vulnerability in the function of request Normalization. The given example works in case of excessive cleaning of incoming data replacement of a regular expression with the empty string. QueryString "id". Negation and inequality signs! An example of various request notations with the same meaning. An example of signature bypass. Some case SQL keyword was filtered out and replaced with whitespace. Which, of course, we can exploit! You can test if the WAF can be crashed by typing:?

If you get ayou can exploit it using the Buffer Overflow Method. So, if you find such a silly function, you can exploit it, in this way. Code: or -' or 1 or '1"or 1 or". Watch Star. The OWASP Foundation works to improve the security of software through its community-led open source software projects, hundreds of chapters worldwide, tens of thousands of members, and by hosting local and global conferences.A web session is a sequence of network HTTP request and response transactions associated to the same user.

Modern and complex web applications require the retaining of information or status about each user for the duration of multiple requests. Therefore, sessions provide the ability to establish variables — such as access rights and localization settings — which will apply to each and every interaction a user has with the web application for the duration of the session.

Web applications can create sessions to keep track of anonymous users after the very first user request. An example would be maintaining the user language preference. Additionally, web applications will make use of sessions once the user has authenticated.

This ensures the ability to identify the user on any subsequent requests as well as being able to apply security access controls, authorized access to the user private data, and to increase the usability of the application. Therefore, current web applications can provide session capabilities both pre and post authentication.

Once an authenticated session has been established, the session ID or token is temporarily equivalent to the strongest authentication method used by the application, such as username and password, passphrases, one-time passwords OTPclient-based digital certificates, smartcards, or biometrics such as fingerprint or eye retina.

HTTP is a stateless protocol RFC section 5where each request and response pair is independent of other web interactions.

XSS Filter Evasion Cheat Sheet

Therefore, in order to introduce the concept of a session, it is required to implement session management capabilities that link both the authentication and access control or authorization modules commonly available in web applications:. The session ID or token binds the user authentication credentials in the form of a user session to the user HTTP traffic and the appropriate access controls enforced by the web application.

The complexity of these three components authentication, session management, and access control in modern web applications, plus the fact that its implementation and binding resides on the web developer's hands as web development framework do not provide strict relationships between these modulesmakes the implementation of a secure session management module very challenging.

The disclosure, capture, prediction, brute force, or fixation of the session ID will lead to session hijacking or sidejacking attacks, where an attacker is able to fully impersonate a victim user in the web application.

Attackers can perform two types of session hijacking attacks, targeted or generic. In a targeted attack, the attacker's goal is to impersonate a specific or privileged web application victim user.

For generic attacks, the attacker's goal is to impersonate or get access as any valid or legitimate user in the web application. In order to keep the authenticated state and track the users progress within the web application, applications provide users with a session identifier session ID or token that is assigned at session creation time, and is shared and exchanged by the user and the web application for the duration of the session it is sent on every HTTP request.

With the goal of implementing secure session IDs, the generation of identifiers IDs or tokens must meet the following properties. The name used by the session ID should not be extremely descriptive nor offer unnecessary details about the purpose and meaning of the ID.

waf bypass cheat sheet

NETetc. Therefore, the session ID name can disclose the technologies and programming languages used by the web application. It is recommended to change the default session ID name of the web development framework to a generic name, such as id.

The session ID must be long enough to prevent brute force attacks, where an attacker can go through the whole range of ID values and verify the existence of valid sessions.An SQL injection cheat sheet is a resource in which you can find detailed technical information about the many different variants of the SQL Injection vulnerability.

This cheat sheet is of good reference to both seasoned penetration tester and also those who are just getting started in web application security. We have updated it and moved it over from our CEO's blog. Some of the samples in this sheet might not work in every situation because real live environments may vary depending on the usage of parenthesis, different code bases and unexpected, strange and complex SQL sentences. Samples are provided to allow you to get basic idea of a potential attack and almost every section includes a brief information about itself.

Comments out rest of the query. Line comments are generally useful for ignoring rest of the query so you don't have to deal with fixing the syntax. Executing more than one query in one transaction. This is very useful in every injection point, especially in SQL Server back ended applications. Can someone clarify? Get response based on an if statement. This is one of the key points of Blind SQL Injectionalso can be very useful to test simple stuff blindly and accurately.

String related operations. These can be quite useful to build up injections which are not using any quotes, bypass any other black listing or determine back end database. With union you do SQL queries cross-table. Basically you can poison query to return records from another table. If application is first getting the record by username and then compare returned MD5 with supplied password's MD5 then you need to some extra tricks to fool application to bypass authentication.

You can union results with a known password and MD5 hash of supplied password. In this case application will compare your password and your supplied MD5 hash instead of MD5 from database. You'll get convert errors before union target errors!

WAF Bypass Cheat Sheet- 2016

So start with convert then union. It's a constant. You can just select it like any other column, you don't need to supply table name.The advantages the web offers resulted in very critical services being developed as web applications. The business requirements for their web applications security has also changed a lot and apart from their good developing standards they add another layer of security. In this blog post I will explain an interesting bypass vector that I found recently during a deployment audit of a WAF.

Recently I was assigned to do a deployment test of a WAF in a company. The architecture of the deployment was something like this:. After I was provided with the required information I started to look for different ways to bypass it.

Once I saw the alert description I started digging more in the documentation of the product and managed to find all the supported SSL ciphers, but before continuing I want to give a quick explanation how an SSL connection works.

The handshake begins by the client which sends a ClientHello message. After receiving the connection the server responds with a ServerHello message which contains similar information that is required by the client. The server also returns what cipher suite and SSL version will be used. After the connection is initialized the server needs to prove its identity to the client. The server sends the SSL certificate to the client and the client checks if it trust the certificate and continues the connection.

Now that a secure tunnel is established the server and client exchange a key which will be used for both encryption and decryption of the data.

The idea that popped in my head was : What if I use an "unsupported" SSL Cipher to initialize the connection to the WebServer which supports that cipher, the WAF would not be able to identify the attack because it can't view the data.

As can be seen below. Comparing the result from sslscan and the documentation of the product, I was able to identify some ciphers which were not supported in the Web Application Firewall but supported in the webserver. The main plan for me before publishing this blogpost was creating a scanner to scan all the supported ciphers, find one which is supposed to bypass the firewall and then start a proxy listener to forward all the requests with that cipher.

Sqli Order by and Hard WAF bypass

During the weekend, I wanted to spend some time brushing up my web appsec skills and decided it would be a good idea to try some CTF challenges. One of the i During our red team operations, we frequently come in contact with organisations using Office The present tooling targeted at this environment is somewh In the recent years APTs have been the center of infosec.Exploit Database.

EDB-ID: EDB Verified:. Author: CWH Underground. Type: papers. Platform: Multiple. Published: Vulnerable App:. This papers will disclose advanced bypassing and obfuscation techniques which many of them can be used in the real CMSs and WAFs. The proposed SQL injection statements in this paper are just some ways to bypass the protection. There are still some other techniques can be used to attacks web applications but unfortunately we cannot tell you right now, as it is kept as a 0-day attack.

However, this paper aims to show that there is no completely secure system in the real world even though you spend more thanUSD on a WAF. This paper is divided into 7 sections but only from section 0x01 to 0x03 are about technical information.

Section 0x01, we give a details of how to bypass filter including basic, function and keyword. Section 0x04, we guide to protect your own website on the right solution.

waf bypass cheat sheet

The last, section 0x05, It's conclusion from Section 0xx Filter Evasion is a technique used to prevent SQL injection attacks. This technique can be done by using a SQL functions and keywords filtering or regular expressions.

This means that filter evasion relies heavily upon how storing a black list or regular expression is. If the black list or regular expression does not cover every injection scenario, the web application is still vulnerable to SQL Injection attacks. If an attackers submits an injection code containing a keyword or SQL function in the black list, the injection will be unsuccessful.While there are a huge number of XSS attack vectors, following a few simple rules can completely defend against this serious attack.

This article does not explore the technical or business impact of XSS. Suffice it to say that it can lead to an attacker gaining the ability to do anything a victim can do through their browser. Both reflected and stored XSS can be addressed by performing the appropriate validation and escaping on the server-side. More background on browser security and the various browsers can be found in the Browser Security Handbook.

Before reading this cheatsheet, it is important to have a fundamental understanding of Injection Theory. This article treats an HTML page like a template, with slots where a developer is allowed to put untrusted data. These slots cover the vast majority of the common places where a developer might want to put untrusted data. Putting untrusted data in other places in the HTML is not allowed.

This is a "whitelist" model, that denies everything that is not specifically allowed. Given the way browsers parse HTML, each of the different types of slots has slightly different security rules.

When you put untrusted data into these slots, you need to take certain steps to make sure that the data does not break out of that slot into a context that allows code execution. In a way, this approach treats an HTML document like a parameterized database query - the data is kept in specific places and is isolated from code contexts with escaping.

This document sets out the most common types of slots and the rules for putting untrusted data into them safely. Based on the various specifications, known XSS vectors, and a great deal of manual testing with all the popular browsers, we have determined that the rules proposed here are safe.

The slots are defined and a few examples of each are provided. Browser parsing is extremely tricky and many innocuous looking characters can be significant in the right context. It even sort of works for untrusted data that goes into attributes, particularly if you're religious about using quotes around your attributes. That's what the rules below are all about. Writing these encoders is not tremendously difficult, but there are quite a few hidden pitfalls.

However, these values are dangerous and may be misinterpreted by the nested parsers in the browser. You might also forget to escape the escape character, which attackers can use to neutralize your attempts to be safe.

OWASP recommends using a security-focused encoding library to make sure these rules are properly implemented. The following rules are intended to prevent all XSS in your application. While these rules do not allow absolute freedom in putting untrusted data into an HTML document, they should cover the vast majority of common use cases.

You do not have to allow all the rules in your organization. Many organizations may find that allowing only Rule 1 and Rule 2 are sufficient for their needs. Please add a note to the discussion page if there is an additional context that is often required and can be secured with escaping.

Do NOT simply escape the list of example characters provided in the various rules. It is NOT sufficient to escape only that list. Blacklist approaches are quite fragile. The whitelist rules here have been carefully designed to provide protection even against future vulnerabilities introduced by browser changes.

The first rule is to deny all - don't put untrusted data into your HTML document unless it is within one of the slots defined in Rule 1 through Rule 5. The reason for Rule 0 is that there are so many strange contexts within HTML that the list of escaping rules gets very complicated. We can't think of any good reason to put untrusted data in these contexts.

This includes "nested contexts" like a URL inside a javascript -- the encoding rules for those locations are tricky and dangerous. If you insist on putting untrusted data into nested contexts, please do a lot of cross-browser testing and let us know what you find out.


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