Exploitation Tools

Ulfberht : Advanced Techniques For Shellcode Loading And Evasion

Ulfberht is a sophisticated shellcode loader designed to enhance operational security and evasion capabilities in cyber operations.

Equipped with features like indirect syscalls, module stomping, and encrypted payloads, it minimizes the digital footprint on targeted systems.

This article delves into Ulfberht’s functionality, offering a step-by-step guide on its deployment and highlighting strategies to avoid detection.

Ideal for security professionals and red teamers, Ulfberht provides a robust framework for executing payloads covertly.

Shellcode Loader

Features :

  • Indirect syscall.
  • Module stomping.
  • Load a stomped module using APC.
  • Execute the payload with a direct jump (jmp) without creating a new thread.
  • API hashing implemented using the DJB2 algorithm.
  • Payload encrypted with RC4 and encoded in UUID format, implemented directly in the loader without loading rpcrt4.dll.
  • No CRT is used.

How to use :

python3 utils.py C:\Path\To\beacon.bin 

Copy the output in payload.h and build the project

NB :

  • If your shellcode lacks evasion features (e.g., Cobalt Strike without UDRL), it can be detected by AV/EDR

Evasion Tips

Compiling this executable and using it directly can be risky, as it may expose potential Indicators of Compromise (IOCs), such as:

  • The file was compiled within the last 5 minutes.
  • The Import Address Table (IAT) is empty.

Also

  • If you’re using a beacon, avoid using an IP for C2 communication. Instead, use a redirector with a good reputation.
  • Add an icon to the executable.
  • Sign the executable; ideally, use a trusted signature.
  • Add delay and sandbox detection.
Varshini

Varshini is a Cyber Security expert in Threat Analysis, Vulnerability Assessment, and Research. Passionate about staying ahead of emerging Threats and Technologies.

Recent Posts

Playwright-MCP : A Powerful Tool For Browser Automation

Playwright-MCP (Model Context Protocol) is a cutting-edge tool designed to bridge the gap between AI…

3 hours ago

JBDev : A Tool For Jailbreak And TrollStore Development

JBDev is a specialized development tool designed to streamline the creation and debugging of jailbreak…

23 hours ago

Kereva LLM Code Scanner : A Revolutionary Tool For Python Applications Using LLMs

The Kereva LLM Code Scanner is an innovative static analysis tool tailored for Python applications…

1 day ago

Nuclei-Templates-Labs : A Hands-On Security Testing Playground

Nuclei-Templates-Labs is a dynamic and comprehensive repository designed for security researchers, learners, and organizations to…

1 day ago

SSH-Stealer : The Stealthy Threat Of Advanced Credential Theft

SSH-Stealer and RunAs-Stealer are malicious tools designed to stealthily harvest SSH credentials, enabling attackers to…

1 day ago

ollvm-unflattener : A Tool For Reversing Control Flow Flattening In OLLVM

Control flow flattening is a common obfuscation technique used by OLLVM (Obfuscator-LLVM) to transform executable…

1 day ago