Category Archives: security

Shellcode: A Tweetable Reverse Shell for x86 Windows

Introduction Since being granted a 280 character limit, many twitter users have been embedding all kinds of code into a single message. This will be a quick post showing a tweetable reverse shell for x86 windows. You’ll have to forgive … Continue reading

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Shellcode: Linux ARM (AArch64)

Introduction I’ve no idea how useful these will be since they were only tested on Linux Ubuntu. They were more or less derived from 32-bit codes shown here, except there’s no attempt at all to eliminate null bytes, and there … Continue reading

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Shellcode: Linux ARM Thumb mode

Introduction Just a quick post about some shellcodes for a raspberry pi 3 I purchased recently to learn ARM assembly. For those interested in developing your own, you can find a full list of Linux system calls in Thumb mode … Continue reading

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WanaCryptor File Encryption and Decryption

Introduction This is a quick post about the WanaCryptor ransomware wreaking havoc on many networks across the world this weekend. With all the news coverage, most of you already know the trouble caused by it. Once executed on a system, … Continue reading

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Shellcode: Dual Mode (x86 + amd64) Linux shellcode

Introduction Someone asked me recently what do you mean by “dual mode shellcode”? and it seems the wording is slightly ambiguous to those unfamiliar with the different operating modes of a CPU like x86 so I just wanted to clarify … Continue reading

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Shellcode: Fido and how it resolves GetProcAddress and LoadLibraryA

Introduction A tool to modify existing metasploit payloads for windows called Fido was recently published by Joshua Pitts, the author of Backdoor Factory. Fido will strip this assembly code responsible for resolving API addresses in the export directory and replace … Continue reading

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Shellcode: Dual mode PIC for x86 (Reverse and Bind Shells for Windows)

Introduction In a nutshell, we’re mixing 32 and 64-bit x86 opcodes so that regardless of the operating system mode (legacy or long), our Position Independent Code (PIC) will still execute successfully. Although some of the code requires conditional jumps, we … Continue reading

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