Malware Analysis Report

2025-03-15 01:11

Sample ID 250226-g6w79avlw4
Target SilverClient.exe
SHA256 ab51ee1b9d05629f8756c9d552a2e182f6273c34a9cb052e9ba5338667bc5a97
Tags
silverrat execution trojan
score
10/10

Table of Contents

Analysis Overview

MITRE ATT&CK

Enterprise Matrix V15

Analysis: static1

Detonation Overview

Signatures

Analysis: behavioral1

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis Overview

score
10/10

SHA256

ab51ee1b9d05629f8756c9d552a2e182f6273c34a9cb052e9ba5338667bc5a97

Threat Level: Known bad

The file SilverClient.exe was found to be: Known bad.

Malicious Activity Summary

silverrat execution trojan

Silverrat family

SilverRat

Executes dropped EXE

Command and Scripting Interpreter: PowerShell

Legitimate hosting services abused for malware hosting/C2

Enumerates physical storage devices

Unsigned PE

Uses Task Scheduler COM API

Delays execution with timeout.exe

Scheduled Task/Job: Scheduled Task

Suspicious behavior: EnumeratesProcesses

Suspicious use of WriteProcessMemory

Suspicious use of SetWindowsHookEx

Suspicious use of AdjustPrivilegeToken

MITRE ATT&CK

Analysis: static1

Detonation Overview

Reported

2025-02-26 06:25

Signatures

Silverrat family

silverrat

Unsigned PE

Description Indicator Process Target
N/A N/A N/A N/A

Analysis: behavioral1

Detonation Overview

Submitted

2025-02-26 06:25

Reported

2025-02-26 06:32

Platform

win11-20250217-en

Max time kernel

399s

Max time network

368s

Command Line

"C:\Users\Admin\AppData\Local\Temp\SilverClient.exe"

Signatures

SilverRat

trojan silverrat

Silverrat family

silverrat

Executes dropped EXE

Description Indicator Process Target
N/A N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe N/A

Command and Scripting Interpreter: PowerShell

execution
Description Indicator Process Target
N/A N/A C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe N/A

Legitimate hosting services abused for malware hosting/C2

Description Indicator Process Target
N/A discord.com N/A N/A
N/A discord.com N/A N/A

Enumerates physical storage devices

Delays execution with timeout.exe

defense_evasion
Description Indicator Process Target
N/A N/A C:\Windows\system32\timeout.exe N/A

Scheduled Task/Job: Scheduled Task

persistence execution
Description Indicator Process Target
N/A N/A C:\Windows\SYSTEM32\schtasks.exe N/A
N/A N/A C:\Windows\System32\schtasks.exe N/A

Suspicious use of AdjustPrivilegeToken

Description Indicator Process Target
Token: SeDebugPrivilege N/A C:\Users\Admin\AppData\Local\Temp\SilverClient.exe N/A
Token: SeDebugPrivilege N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe N/A
Token: SeDebugPrivilege N/A C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe N/A

Suspicious use of SetWindowsHookEx

Description Indicator Process Target
N/A N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe N/A

Suspicious use of WriteProcessMemory

Description Indicator Process Target
PID 5028 wrote to memory of 2036 N/A C:\Users\Admin\AppData\Local\Temp\SilverClient.exe C:\Windows\system32\cmd.exe
PID 5028 wrote to memory of 2036 N/A C:\Users\Admin\AppData\Local\Temp\SilverClient.exe C:\Windows\system32\cmd.exe
PID 2036 wrote to memory of 228 N/A C:\Windows\system32\cmd.exe C:\Windows\system32\timeout.exe
PID 2036 wrote to memory of 228 N/A C:\Windows\system32\cmd.exe C:\Windows\system32\timeout.exe
PID 2036 wrote to memory of 3820 N/A C:\Windows\system32\cmd.exe C:\Users\Admin\HP_Drivers\HP_Updates.exe
PID 2036 wrote to memory of 3820 N/A C:\Windows\system32\cmd.exe C:\Users\Admin\HP_Drivers\HP_Updates.exe
PID 3820 wrote to memory of 1268 N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe C:\Windows\SYSTEM32\schtasks.exe
PID 3820 wrote to memory of 1268 N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe C:\Windows\SYSTEM32\schtasks.exe
PID 3820 wrote to memory of 4792 N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe C:\Windows\SYSTEM32\schtasks.exe
PID 3820 wrote to memory of 4792 N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe C:\Windows\SYSTEM32\schtasks.exe
PID 3820 wrote to memory of 1876 N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe C:\Windows\SYSTEM32\schtasks.exe
PID 3820 wrote to memory of 1876 N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe C:\Windows\SYSTEM32\schtasks.exe
PID 3820 wrote to memory of 1048 N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
PID 3820 wrote to memory of 1048 N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
PID 3820 wrote to memory of 2444 N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe C:\Windows\System32\schtasks.exe
PID 3820 wrote to memory of 2444 N/A C:\Users\Admin\HP_Drivers\HP_Updates.exe C:\Windows\System32\schtasks.exe

Uses Task Scheduler COM API

persistence

Processes

C:\Users\Admin\AppData\Local\Temp\SilverClient.exe

"C:\Users\Admin\AppData\Local\Temp\SilverClient.exe"

C:\Windows\system32\cmd.exe

C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmp9F4D.tmp.bat""

C:\Windows\system32\timeout.exe

timeout 3

C:\Users\Admin\HP_Drivers\HP_Updates.exe

"C:\Users\Admin\HP_Drivers\HP_Updates.exe"

C:\Windows\SYSTEM32\schtasks.exe

"schtasks.exe" /query /TN HP_Updates.exe

C:\Windows\SYSTEM32\schtasks.exe

"schtasks.exe" /Create /SC ONCE /TN "HP_Updates.exe" /TR "C:\Users\Admin\HP_Drivers\HP_Updates.exe \"\HP_Updates.exe\" /AsAdmin" /ST 00:01 /IT /F /RL HIGHEST

C:\Windows\SYSTEM32\schtasks.exe

"schtasks.exe" /query /TN HP_Updates.exe

C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe

"C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" Set-MpPreference -ExclusionExtension exe,bat,dll,ps1;exit

C:\Windows\System32\schtasks.exe

"C:\Windows\System32\schtasks.exe" /create /sc hourly /mo 1 /tn "HP_Updates_Task-HOURLY-01" /tr "%MyFile%" /st 00:00

Network

Country Destination Domain Proto
US 8.8.8.8:53 discord.com udp
US 162.159.137.232:443 discord.com tcp

Files

memory/5028-0-0x00007FFF6C253000-0x00007FFF6C255000-memory.dmp

memory/5028-1-0x00000000007C0000-0x00000000007D0000-memory.dmp

memory/5028-2-0x00007FFF6C250000-0x00007FFF6CD12000-memory.dmp

memory/5028-7-0x00007FFF6C250000-0x00007FFF6CD12000-memory.dmp

C:\Users\Admin\AppData\Local\Temp\tmp9F4D.tmp.bat

MD5 58168925dc562a42ac66db33978be0d9
SHA1 7378caeae938f8beea60e30498d6210d5307b20f
SHA256 267730a31294570c6541e2e7844ac50260b7a52ae14def5d3e2a923b8b9b577d
SHA512 493a8c06b7322b4715ea9140552f3a2aa3f42279526e3c961092da4645cc8401ce56c157c55a349fc4caebdcf30171015d802a79c98cd17303a54dc8a076d618

C:\Users\Admin\HP_Drivers\HP_Updates.exe

MD5 c312ff9dfd199ae5b504932e018b4d84
SHA1 75ff47cc5fb04726d14df93b9c8804360a74f4ad
SHA256 ab51ee1b9d05629f8756c9d552a2e182f6273c34a9cb052e9ba5338667bc5a97
SHA512 94a1e811451022abc9e408c5ede051d9656ce74383455b3ecb897dba9c1abf1bac21447b42ece811845271639de201d780b9aaab594615636fc59538be3684a7

memory/3820-12-0x00007FFF6C250000-0x00007FFF6CD12000-memory.dmp

memory/3820-13-0x00007FFF6C250000-0x00007FFF6CD12000-memory.dmp

C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_1sm40r3i.4fd.ps1

MD5 d17fe0a3f47be24a6453e9ef58c94641
SHA1 6ab83620379fc69f80c0242105ddffd7d98d5d9d
SHA256 96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7
SHA512 5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

memory/1048-22-0x0000021A46300000-0x0000021A46322000-memory.dmp

memory/3820-25-0x00007FFF6C250000-0x00007FFF6CD12000-memory.dmp

memory/3820-26-0x00007FFF6C250000-0x00007FFF6CD12000-memory.dmp