juko | c2f8a425e1d7cefd48fa2b8c92bfc07df86c3afaf4bfa4d86d7a1ced20e2bae2

General

Target
2026-08-03_f39d6fdb0faf962af158424814f32151_elex_wannacry.exe
Size 87KB
Sample260803-y51bysfb97
SHA256 c2f8a425e1d7cefd48fa2b8c92bfc07df86c3afaf4bfa4d86d7a1ced20e2bae2
MD5 f39d6fdb0faf962af158424814f32151
SHA1 9d61ae11cf70ec818b4553783b2d10fd3dddff2e
SHA512 7065366395faaa646949bece3a7aff1192c099a632ea1c9b0e20e28b5f49ce0f72776476aace47c3cf13f71d816375af3746e5e82c372b2a5346530cbbc7c285
SSDEEP 1536:2LsF2Kerc64sTiX2IV0DpK8SE9nYOzmEQkwpc:2Ly2Kerc64CiGIm1K851YO6EQkwpc
TLSH
T1BB93A1763A259190C48BD178E8155AA0B932DCF52FF71303E6417AAC59B1E13CFAE8C6
MD5 SHA1 SHA512 SSDEEP TLSH

Score

10^/10

discovery execution juko persistence trojan

Malware Config

Signatures

Family: Juko
Juko is a trojan written in C++.
trojan juko

Detects Juko 8 IoCs

resource	yara_rule
behavioral1/memory/2104-0-0x0000000000400000-0x0000000000425000-memory.dmp	family_juko
behavioral1/files/0x000e0000000242c7-5.dat	family_juko
behavioral1/memory/1920-11-0x0000000000400000-0x0000000000425000-memory.dmp	family_juko
behavioral1/memory/2104-12-0x0000000000400000-0x0000000000425000-memory.dmp	family_juko
behavioral1/memory/1920-15-0x0000000000400000-0x0000000000425000-memory.dmp	family_juko
behavioral1/files/0x00080000000244b8-16.dat	family_juko
behavioral1/memory/3080-18-0x0000000000400000-0x0000000000425000-memory.dmp	family_juko
behavioral1/memory/3080-19-0x0000000000400000-0x0000000000425000-memory.dmp	family_juko

Checks computer location settings 2 TTPs 2 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-1-5-21-1788976790-1541110888-1636651838-1000\Control Panel\International\Geo\Nation	2026-08-03_f39d6fdb0faf962af158424814f32151_elex_wannacry.exe
Key value queried	\REGISTRY\USER\S-1-5-21-1788976790-1541110888-1636651838-1000\Control Panel\International\Geo\Nation	WINWORD.exe

Executes dropped EXE 2 IoCs

pid	Process
1920	WINWORD.exe
3080	WINWORD.exe

Adds Run key to start application 2 TTPs 1 IoCs

persistence

Registry Run Keys / Startup Folder

T1547.001

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\USER\S-1-5-21-1788976790-1541110888-1636651838-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\WINWORD = "C:\\Users\\Admin\\AppData\\Roaming\\Mozilla\\WINWORD.exe -r"	WINWORD.exe

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

System Information Discovery
T1082

Executes a command shell one-liner 1 TTPs 1 IoCs

Execution of a cmd.exe one-liner (/c "close" or /k "keep") is a common script/loader stage.

execution

Windows Command Shell

T1059.003

pid	Process
2888	cmd.exe

System Location Discovery: System Language Discovery 1 TTPs 7 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	WINWORD.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	PING.EXE
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	PING.EXE
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	PING.EXE
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	WINWORD.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	2026-08-03_f39d6fdb0faf962af158424814f32151_elex_wannacry.exe

System Network Configuration Discovery: Internet Connection Discovery 1 TTPs 4 IoCs

Adversaries may check for Internet connectivity on compromised systems.

discovery

Internet Connection Discovery

T1016.001

pid	Process
2888	cmd.exe
4784	PING.EXE
2284	PING.EXE
2184	PING.EXE

Runs ping.exe 1 TTPs 3 IoCs

Remote System Discovery

T1018

pid	Process
4784	PING.EXE
2284	PING.EXE
2184	PING.EXE

Suspicious use of WriteProcessMemory 6 IoCs

description	pid	Process	procid_target
PID 2104 wrote to memory of 1920	2104	2026-08-03_f39d6fdb0faf962af158424814f32151_elex_wannacry.exe	85
PID 1920 wrote to memory of 2888	1920	WINWORD.exe	86
PID 2888 wrote to memory of 4784	2888	cmd.exe	88
PID 2888 wrote to memory of 2284	2888	cmd.exe	89
PID 2888 wrote to memory of 2184	2888	cmd.exe	92
PID 2888 wrote to memory of 3080	2888	cmd.exe	95

C:\Users\Admin\AppData\Local\Temp\2026-08-03_f39d6fdb0faf962af158424814f32151_elex_wannacry.exe
"C:\Users\Admin\AppData\Local\Temp\2026-08-03_f39d6fdb0faf962af158424814f32151_elex_wannacry.exe"
1⤵
- Checks computer location settings
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:2104
- C:\Users\Admin\AppData\Roaming\Mozilla\WINWORD.exe
  "C:\Users\Admin\AppData\Roaming\Mozilla\WINWORD.exe" -r
  2⤵
  - Checks computer location settings
  - Executes dropped EXE
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:1920
- - C:\Windows\SysWOW64\cmd.exe
    "C:\Windows\System32\cmd.exe" /c ping 127.0.0.1 -n 2&del "C:\Users\Admin\AppData\Roaming\Mozilla\WINWORD.exe"&ping 127.0.0.1 -n 2&rename "C:\Users\Admin\AppData\Roaming\Mozilla\00000561" WINWORD.exe&ping 127.0.0.1 -n 2&"C:\Users\Admin\AppData\Roaming\Mozilla\WINWORD.exe" \r
    3⤵
    - Executes a command shell one-liner
    - System Location Discovery: System Language Discovery
    - System Network Configuration Discovery: Internet Connection Discovery
    - Suspicious use of WriteProcessMemory
    PID:2888
  - - C:\Windows\SysWOW64\PING.EXE
      ping 127.0.0.1 -n 2
      4⤵
      System Location Discovery: System Language Discovery
      System Network Configuration Discovery: Internet Connection Discovery
      Runs ping.exe
      PID:4784
  - - C:\Windows\SysWOW64\PING.EXE
      ping 127.0.0.1 -n 2
      4⤵
      System Location Discovery: System Language Discovery
      System Network Configuration Discovery: Internet Connection Discovery
      Runs ping.exe
      PID:2284
  - - C:\Windows\SysWOW64\PING.EXE
      ping 127.0.0.1 -n 2
      4⤵
      System Location Discovery: System Language Discovery
      System Network Configuration Discovery: Internet Connection Discovery
      Runs ping.exe
      PID:2184
  - - C:\Users\Admin\AppData\Roaming\Mozilla\WINWORD.exe
      "C:\Users\Admin\AppData\Roaming\Mozilla\WINWORD.exe" \r
      4⤵
      Executes dropped EXE
      Adds Run key to start application
      System Location Discovery: System Language Discovery
      PID:3080

Network

MITRE ATT&CK Enterprise v16

Reconnaissance

Resource Development

Initial Access

Execution

Command and Scripting Interpreter

1

T1059

Windows Command Shell

1

T1059.003

Persistence

Boot or Logon Autostart Execution

1

T1547

Registry Run Keys / Startup Folder

1

T1547.001

Privilege Escalation

Boot or Logon Autostart Execution

1

T1547

Registry Run Keys / Startup Folder

1

T1547.001

Defense Evasion

Modify Registry

1

T1112

Credential Access

Discovery

Query Registry

1

T1012

Remote System Discovery

1

T1018

System Information Discovery

2

T1082

System Location Discovery

1

T1614

System Language Discovery

1

T1614.001

System Network Configuration Discovery

1

T1016

Internet Connection Discovery

1

T1016.001

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

00000561

Path C:\Users\Admin\AppData\Roaming\Mozilla\00000561
Size 87KB
SHA256 948ef2470fbf55fea7c55116309778ded0affd43e68352d115f260e34c2947da
MD5 e2301cd757ca4a76d4ad2fc697574d06
SHA1 d7294c71fffb421a0a2643bdea3cd5deb5591765
SHA512 9227e790dfecce4fa99d61cc3de0b5bc79473c1058489808c0ee5566c59cf48bfde67eb9c4f082a19019a44199361c4ad1b28d2c38e8d067038e4f8476c28505
SSDEEP 1536:2LsF2Kerc64sTiX2IV0DpK8SE9nYOzmEQkwpI:2Ly2Kerc64CiGIm1K851YO6EQkwpI
TLSH
T14E93A1763A259190C48BD178E8155AA0B932DCF52FF71303E6417AAC59B1E13CFAE8C6
MD5 SHA1 SHA512 SSDEEP TLSH

Submit Download

WINWORD.exe

Path C:\Users\Admin\AppData\Roaming\Mozilla\WINWORD.exe
Size 87KB
SHA256 c2f8a425e1d7cefd48fa2b8c92bfc07df86c3afaf4bfa4d86d7a1ced20e2bae2
MD5 f39d6fdb0faf962af158424814f32151
SHA1 9d61ae11cf70ec818b4553783b2d10fd3dddff2e
SHA512 7065366395faaa646949bece3a7aff1192c099a632ea1c9b0e20e28b5f49ce0f72776476aace47c3cf13f71d816375af3746e5e82c372b2a5346530cbbc7c285
SSDEEP 1536:2LsF2Kerc64sTiX2IV0DpK8SE9nYOzmEQkwpc:2Ly2Kerc64CiGIm1K851YO6EQkwpc
TLSH
T1BB93A1763A259190C48BD178E8155AA0B932DCF52FF71303E6417AAC59B1E13CFAE8C6
MD5 SHA1 SHA512 SSDEEP TLSH

Submit Download

memory/1920-11-0x0000000000400000-0x0000000000425000-memory.dmp

Download

memory/1920-15-0x0000000000400000-0x0000000000425000-memory.dmp

Download

memory/2104-0-0x0000000000400000-0x0000000000425000-memory.dmp

Download

memory/2104-12-0x0000000000400000-0x0000000000425000-memory.dmp

Download

memory/3080-18-0x0000000000400000-0x0000000000425000-memory.dmp

Download

memory/3080-19-0x0000000000400000-0x0000000000425000-memory.dmp

Download

Analysis

Sharing

General

Malware Config

Signatures

Processes

Network

MITRE ATT&CK Enterprise v16

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Downloads