ostap | 843021e4a2dcaa8887c2e0945157f947dbfd81372d601be47416294355635496

Analysis

max time kernel
155s
max time network
150s
platform
windows10-2004_x64
resource
win10v2004-en-20220112
submitted
01-02-2022 05:19

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General

Target

843021e4a2dcaa8887c2e0945157f947dbfd81372d601be47416294355635496.xlsm
Size

388KB
MD5

dcf3d45ddee53a91d55c45614124f0f1
SHA1

ac8889a3cbf370edf067029df9eb12e16aab5a81
SHA256

843021e4a2dcaa8887c2e0945157f947dbfd81372d601be47416294355635496
SHA512

15e8e146253488949468c30a999af89b88f086482a2e7ea610ba32084eb1c28930bd8b2a8b05631c425c275873ee81acda1d86b1c33514f05190ba5bd9fd95c2

Score

10^/10

ostap downloader persistence

Malware Config

Signatures

Ostap JavaScript Downloader 1 IoCs

Ostap is a JavaScript downloader that's been active since 2016. It's used to deliver several families, inluding TrickBot

resource	yara_rule
behavioral2/files/0x0003000000021835-262.dat	family_ostap

Process spawned unexpected child process 1 IoCs

This typically indicates the parent process was compromised via an exploit or macro.

description	pid	pid_target	Process	procid_target
Parent C:\Program Files\Microsoft Office\Root\Office16\EXCEL.EXE is not expected to spawn this process	1756	912	explorer.exe	51

ostap
Ostap is a JS downloader, used to deliver other families.
downloader ostap
Sets service image path in registry 2 TTPs
persistence

Registry Run Keys / Startup Folder
T1060

Modify Registry
T1112

Checks processor information in registry 2 TTPs 3 IoCs

Processor information is often read in order to detect sandboxing environments.

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key opened	\REGISTRY\MACHINE\Hardware\Description\System\CentralProcessor\0	EXCEL.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\~MHz	EXCEL.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\ProcessorNameString	EXCEL.EXE

Enumerates system info in registry 2 TTPs 3 IoCs

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key opened	\REGISTRY\MACHINE\Hardware\Description\System\BIOS	EXCEL.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\BIOS\SystemFamily	EXCEL.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\BIOS\SystemSKU	EXCEL.EXE

Modifies data under HKEY_USERS 41 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\CA\CRLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\Root	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\SmartCardRoot\CRLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\trust	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\CA\CTLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\Disallowed	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\SmartCardRoot\Certificates	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\TrustedPeople\CRLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\TrustedPeople	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\TrustedPeople\CTLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\trust\Certificates	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\trust\CTLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\CA\CTLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\trust	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\Disallowed\CRLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\Disallowed\CRLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\Disallowed\CTLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\TrustedPeople\Certificates	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\Disallowed\Certificates	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\CA	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\Disallowed\CTLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\Root\CTLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\TrustedPeople	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\WinTrust\Trust Providers\Software Publishing	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\SmartCardRoot	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\TrustedPeople\CRLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\trust\Certificates	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\CA	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\Root\CRLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\SmartCardRoot\CTLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\TrustedPeople\CTLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\trust\CTLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\Disallowed	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\Root\Certificates	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\TrustedPeople\Certificates	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\trust\CRLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\trust\CRLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\Disallowed\Certificates	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\CA\CRLs	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Policies\Microsoft\SystemCertificates\CA\Certificates	WaaSMedicAgent.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\SystemCertificates\CA\Certificates	WaaSMedicAgent.exe

Modifies registry class 1 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-790714498-1549421491-1643397139-1000_Classes\Local Settings	explorer.exe

Suspicious behavior: AddClipboardFormatListener 1 IoCs

pid	Process
912	EXCEL.EXE

Suspicious use of SetWindowsHookEx 14 IoCs

pid	Process
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE
912	EXCEL.EXE

Suspicious use of WriteProcessMemory 4 IoCs

description	pid	Process	procid_target
PID 912 wrote to memory of 1756	912	EXCEL.EXE	63
PID 912 wrote to memory of 1756	912	EXCEL.EXE	63
PID 3312 wrote to memory of 2268	3312	explorer.exe	66
PID 3312 wrote to memory of 2268	3312	explorer.exe	66

C:\Program Files\Microsoft Office\Root\Office16\EXCEL.EXE
"C:\Program Files\Microsoft Office\Root\Office16\EXCEL.EXE" "C:\Users\Admin\AppData\Local\Temp\843021e4a2dcaa8887c2e0945157f947dbfd81372d601be47416294355635496.xlsm"
1⤵
- Checks processor information in registry
- Enumerates system info in registry
- Suspicious behavior: AddClipboardFormatListener
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:912
- C:\Windows\explorer.exe
  "C:\Windows\explorer.exe" "C:\Users\Admin\AppData\Roaming\Microsoft\Excel\XLSTART\..\..\..\..\..\5034o.sedrtgyh.jse"
  2⤵
  - Process spawned unexpected child process
  PID:1756

C:\Windows\system32\svchost.exe
C:\Windows\system32\svchost.exe -k LocalServiceAndNoImpersonation -p
1⤵
PID:2352

C:\Windows\System32\WaaSMedicAgent.exe
C:\Windows\System32\WaaSMedicAgent.exe f34ab0d7710b7245e9fb20f229f77ef5 neWrerG0IkW2h9X5MLBNpw.0.1.0.0.0
1⤵
- Modifies data under HKEY_USERS
PID:2676

C:\Windows\explorer.exe
C:\Windows\explorer.exe /factory,{75dff2b7-6936-4c06-a8bb-676a7b00b24b} -Embedding
1⤵
- Modifies registry class
- Suspicious use of WriteProcessMemory
PID:3312
- C:\Windows\System32\WScript.exe
  "C:\Windows\System32\WScript.exe" "C:\Users\Admin\5034o.sedrtgyh.jse"
  2⤵
  PID:2268

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Registry Run Keys / Startup Folder

T1060

Privilege Escalation

Defense Evasion

Modify Registry

T1112

Credential Access

Discovery

Query Registry

T1012

System Information Discovery

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

memory/912-133-0x00007FFF2C470000-0x00007FFF2C480000-memory.dmp

Filesize
64KB

Download
memory/912-134-0x00007FFF2C470000-0x00007FFF2C480000-memory.dmp

Filesize
64KB

Download
memory/912-135-0x00007FFF2C470000-0x00007FFF2C480000-memory.dmp

Filesize
64KB

Download
memory/912-136-0x00007FFF2C470000-0x00007FFF2C480000-memory.dmp

Filesize
64KB

Download
memory/912-137-0x00007FFF2C470000-0x00007FFF2C480000-memory.dmp

Filesize
64KB

Download
memory/912-140-0x00007FFF29F50000-0x00007FFF29F60000-memory.dmp

Filesize
64KB

Download
memory/912-141-0x00007FFF29F50000-0x00007FFF29F60000-memory.dmp

Filesize
64KB

Download
memory/912-154-0x00000170FF030000-0x00000170FF034000-memory.dmp

Filesize
16KB

Download

Analysis

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General

Malware Config

Signatures

Processes

Network

MITRE ATT&CK Enterprise v6

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Downloads