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Burp Suite vs CSRF Tokens: CSRFTEI

I wrote a very simple burp extension that can pull a token a CSRF token out of a response and update the next request with that token. It’s designed to be a simple as possible so it works for my lesson on writing burp extensions and if you’re lucky then all you need to do is update the script with the name of the token your target application uses and you’re good to go but it’s designed to be as easy to tweak to your needs as possible. I also wrote about how to install custom extensions here if you’ve not done that before, just copy and paste the below code into a file called csrftei.py and load that file into burp! The code is all available below and should be nicely commented to explain how everything works:

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Burp Macros: Automatic Re-authentication

During a recent penetration test I came up against a security feature that would invalidate my session whilst I was fuzzing if it saw simple attack strings, so if I used <script> anywhere then it’d kill my session. Most frustrating! Especially as it essentially prevented the use of tools such as Burp’s Active Scanner and it made using Repeater inconvenient too. So I quickly threw together a Burp Macro to handle automatic re-authentication for me and went back to fuzzing!

So here’s how to do that!

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Web Application Defense: Filtering User Input

Effectively filtering user input is one of the best ways to prevent an awful lot of web application vulnerabilities. There are several ways to approach this, each with their own pros and cons so I’ll run through them here an then you can think of the best way to combine them for your context. It’s important to remember though, that filters are context specific, there is not one filter that will work for a whole application and that’s what can make writing an effective filter tricky.

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SQL Injection: Basics and Defence

Structured Query Language (SQL) is used all over the web and is potentially vulnerable to an injection attack any time that user input is insecurely concatenated into a query. An injection attack allows an attacker to alter the logic of the query and the attack can lead to confidential data theft, website defacement, malware propagation and host/network compromise.

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