THM - Advent of Cyber 2022 - Day 15

Difficulty:
Challenge Link
OS: Linux

Learning Objectives Input validation of file upload functionality Unrestricted file upload vulnerabilities Phishing through file uploads How to properly secure file upload functionality

What is the name given to file uploads that allow threat actors to upload any files that they want?

Refer to the beginning of the module where it talks about this.

Answer

Unrestricted

What is the title of the web application developed by Santa's freelancer?

Start the Machine and navigate to the MACHINE_IP to see the web application loaded and read the name it top left.

Answer

SantaSideKick2

What is the value of the flag stored in the HR Elf's Documents directory?

Follow the msfvenom steps in the module to generate a malicious .exe that gives us a Reverse Shell

Answer

THM{Naughty.File.Uploads.Can.Get.You.RCE}

What defence technique can be implemented to ensure that specific file types can be uploaded?

Answer

File Extension Validation

What defence technique can be used to make sure the threat actor cannot recover their file again by simply using the file name?

Answer

File Renaming

What defence technique can be used to make sure malicious files that can hurt elves are not uploaded?

Answer

Malware Scanning