silverrat | 4008b0c3754f16bdf1365b0f894e48c82ccf5f8a656592fab4db899e11b73051

General

Target

SilverClient.exe
Size

42KB
MD5

953679a46f8bada4aea3c89e2026176a
SHA1

b78419d85a443d21fdd3bd6673c6c0b407f615da
SHA256

4008b0c3754f16bdf1365b0f894e48c82ccf5f8a656592fab4db899e11b73051
SHA512

4aabe38b1c404c4d61b08b4126bf509dc81cf50131db2c1061452cd795cc6c1f05055b03f8cadf99aa2b76f0f5c36fc3babe0cbb0a9d978a38fb71ca5f7ecd96
SSDEEP

768:GiImvwcOx/MUpJRBc/u+cJn6550BcmSHrlruPXr7yaaxLEt0URoPRULL9SI1PCBn:GiImIcOBBdn655XTkt0U2Gf9XKo39ZU

Score

10^/10

silverrat execution persistence trojan

Malware Config

Extracted

Family

silverrat

Version

1.0.0.0

C2

hope-asia.gl.at.ply.gg:35710

Mutex

SilverMutex_RxkTUhToXD

Attributes

certificate
MIIE4DCCAsigAwIBAgIQAKQYOfZd86J2BfNjhG4CWTANBgkqhkiG9w0BAQ0FADARMQ8wDQYDVQQDDAZTaWx2ZXIwIBcNMjIwODI2MTkwMTA4WhgPOTk5OTEyMzEyMzU5NTlaMBExDzANBgNVBAMMBlNpbHZlcjCCAiIwDQYJKoZIhvcNAQEBBQADggIPADCCAgoCggIBAPbpOWfhZTuOfEaqqImTTe5dNHAAry7/mf00DCoI4lPZfypsc1tYraxSPFeayGu09a3qdhkWKSVIgwnu2n4GLQNOCY9fh/1oyrX4Iir3BIkYeU7pKTWgjhUlAmFAUAaNr0ca23Ku2kN79jrDzRznOgE2DEW4p7OiM4Mb097ma9lzu7MyssHbY4VCteAhj9HZiplqBxaC1vXDmzxqG+gUZ1aLcyG7ssdkOjtWVBgT3gD/gOl7KchRzCFB1egDC/vD9WZCG35U3Ngi+IkTznoXR1R06cq4v0UnGjE37R2vcB21qb0ZYNiZJXZHv5i9+R7xoPeNoLda5PqnfGGbhPvNEdD56mdcOKlzGIuyemLkUo8texdpiBWKbtc3JZf5VsKxjJtHDK3xW6gDGI+PAirzGkFPmwcf8WgsblvzLg8OZpVxVs8rmKWoi6qIrf4CXnyl73J4lgzW+ir7PjANAQXwLNGdNnvdMeLeo/muGQPdeNpr6OczGGnkWA4qniHeL51/Gx0a8A+jP9zKiyu+qHcsP2IotgWDH/KlzJVr7IAum+DV92uV8poTDcUNcHaKvhHA65KmEtsvLbK6lFZcAMC0eWC0VgpW44T1/16rOaaky5mP6rTMc3nSyOl/lU/XgAgGGQPe22bRLWYzd3WVeEpI1WnHYXS+tL9IOe4kJP+pYsWDAgMBAAGjMjAwMB0GA1UdDgQWBBR32TJj2LeUx9L+RcSOvmFV6VJq6TAPBgNVHRMBAf8EBTADAQH/MA0GCSqGSIb3DQEBDQUAA4ICAQA+qucSOi7ov7Q1FmAjMf925KuvKuCNwJiu3Sqo3FDGVAD1fAwAi2FdyuXEO2VIUPZCkalFcBna5rqyrc6tcS4T0IL2TsYLrsuGir7PWP7CAcft1urYS1HpNpHxeH/nixwnQaQs/MuRmdm2TeCj6G21P5BTW55U5y9sMPSYwhbD2N7XLgnSQd5Y+80TR7FUiye/k3D37fI9PRhSQGbfYFRQQTmxj84dPTnY5CVgaY9d8fNiFZkyjaZdf+mibK0xQTf+xLVVj+toDNCkc1F462TdmFhCrHd4PoMo0yLDNv4SC6NLRq4haWDRtORw6gd5GYIoCQ3m3oQvNlNxXhhIjsOyxkxOrkCD0c+57PIc7EmKXieJa/XxnkcIVxO8dvTY/vijuz/VaZYl/lPu9ckuqgJ1wRvvsHl70Trv4Mn4X5uCIqRFFlK/mSOZbLIguGkDN3QIZABvej89vlZMhrVfZOG2oawe23FskHjv7thF/WzOXtWw6RUVC1V+hCwbuxFNUjZmmOTUwdXHnus7I2AuiG6Jz1+y9aYiXBcVTdSljxjHRRmiRaAnY94h58vN8NJ4hKL2GVCo6LxkpuplmcntJN0cKraKTPxSXcCRrqWxX9qoIbfvBcUU4vH1jPJCCLNCuDyD3lgQkpPVvq0EMU1a2HFGgMEQMjpYpb38rcadDhT5ag==
decrypted_key
-|S.S.S|-
key
yy6zDjAUmbB09pKvo5Hhug==
key_x509
TVRpQXhBRVBpd1liZHFlUlNEQ0FEbVd4Z3JKU1JN
reconnect_delay
4
server_signature
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

Signatures

SilverRat
SilverRat is trojan written in C#.
trojan silverrat
Silverrat family
silverrat

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-1-5-21-3350944739-639801879-157714471-1000\Control Panel\International\Geo\Nation	$77SystemUser.exe.exe

Executes dropped EXE 1 IoCs

pid	Process
3632	$77SystemUser.exe.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\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\ = "\"C:\\Users\\Admin\\SystemUser.exe\\$77SystemUser.exe.exe\""	SilverClient.exe

Command and Scripting Interpreter: PowerShell 1 TTPs 1 IoCs

Using powershell.exe command.

execution

PowerShell

T1059.001

pid	Process
1604	powershell.exe

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

System Information Discovery
T1082

Delays execution with timeout.exe 1 IoCs

evasion

pid	Process
4716	timeout.exe

Scheduled Task/Job: Scheduled Task 1 TTPs 2 IoCs

Schtasks is often used by malware for persistence or to perform post-infection execution.

persistence execution

Scheduled Task

T1053.005

pid	Process
3724	schtasks.exe
5052	schtasks.exe

Suspicious behavior: EnumeratesProcesses 26 IoCs

pid	Process
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
2356	SilverClient.exe
3632	$77SystemUser.exe.exe
1604	powershell.exe
1604	powershell.exe

Suspicious use of AdjustPrivilegeToken 6 IoCs

description	pid	Process
Token: SeBackupPrivilege	4448	vssvc.exe
Token: SeRestorePrivilege	4448	vssvc.exe
Token: SeAuditPrivilege	4448	vssvc.exe
Token: SeDebugPrivilege	2356	SilverClient.exe
Token: SeDebugPrivilege	3632	$77SystemUser.exe.exe
Token: SeDebugPrivilege	1604	powershell.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
3632	$77SystemUser.exe.exe

Suspicious use of WriteProcessMemory 16 IoCs

description	pid	Process	procid_target
PID 2356 wrote to memory of 1212	2356	SilverClient.exe	101
PID 2356 wrote to memory of 1212	2356	SilverClient.exe	101
PID 1212 wrote to memory of 4716	1212	cmd.exe	103
PID 1212 wrote to memory of 4716	1212	cmd.exe	103
PID 1212 wrote to memory of 3632	1212	cmd.exe	104
PID 1212 wrote to memory of 3632	1212	cmd.exe	104
PID 3632 wrote to memory of 3088	3632	$77SystemUser.exe.exe	108
PID 3632 wrote to memory of 3088	3632	$77SystemUser.exe.exe	108
PID 3632 wrote to memory of 3724	3632	$77SystemUser.exe.exe	110
PID 3632 wrote to memory of 3724	3632	$77SystemUser.exe.exe	110
PID 3632 wrote to memory of 2740	3632	$77SystemUser.exe.exe	112
PID 3632 wrote to memory of 2740	3632	$77SystemUser.exe.exe	112
PID 3632 wrote to memory of 1604	3632	$77SystemUser.exe.exe	114
PID 3632 wrote to memory of 1604	3632	$77SystemUser.exe.exe	114
PID 3632 wrote to memory of 5052	3632	$77SystemUser.exe.exe	115
PID 3632 wrote to memory of 5052	3632	$77SystemUser.exe.exe	115

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
Uses Volume Shadow Copy service COM API
The Volume Shadow Copy service is used to manage backups/snapshots.
ransomware

C:\Users\Admin\AppData\Local\Temp\SilverClient.exe
"C:\Users\Admin\AppData\Local\Temp\SilverClient.exe"
1⤵
- Adds Run key to start application
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:2356
- C:\Windows\system32\cmd.exe
  C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmpCDDF.tmp.bat""
  2⤵
  - Suspicious use of WriteProcessMemory
  PID:1212
- - C:\Windows\system32\timeout.exe
    timeout 3
    3⤵
    - Delays execution with timeout.exe
    PID:4716
- - C:\Users\Admin\SystemUser.exe\$77SystemUser.exe.exe
    "C:\Users\Admin\SystemUser.exe\$77SystemUser.exe.exe"
    3⤵
    - Checks computer location settings
    - Executes dropped EXE
    - Suspicious behavior: EnumeratesProcesses
    - Suspicious use of AdjustPrivilegeToken
    - Suspicious use of SetWindowsHookEx
    - Suspicious use of WriteProcessMemory
    PID:3632
  - - C:\Windows\SYSTEM32\schtasks.exe
      "schtasks.exe" /query /TN $77SystemUser.exe.exe
      4⤵
      PID:3088
  - - C:\Windows\SYSTEM32\schtasks.exe
      "schtasks.exe" /Create /SC ONCE /TN "$77SystemUser.exe.exe" /TR "C:\Users\Admin\SystemUser.exe\$77SystemUser.exe.exe \"\$77SystemUser.exe.exe\" /AsAdmin" /ST 00:01 /IT /F /RL HIGHEST
      4⤵
      Scheduled Task/Job: Scheduled Task
      PID:3724
  - - C:\Windows\SYSTEM32\schtasks.exe
      "schtasks.exe" /query /TN $77SystemUser.exe.exe
      4⤵
      PID:2740
  - - C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
      "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" Set-MpPreference -ExclusionExtension exe,bat,dll,ps1;exit
      4⤵
      Command and Scripting Interpreter: PowerShell
      Suspicious behavior: EnumeratesProcesses
      Suspicious use of AdjustPrivilegeToken
      PID:1604
  - - C:\Windows\System32\schtasks.exe
      "C:\Windows\System32\schtasks.exe" /create /sc hourly /mo 1 /tn "SystemUser.exe_Task-HOURLY-01" /tr "%MyFile%" /st 00:00
      4⤵
      Scheduled Task/Job: Scheduled Task
      PID:5052

C:\Windows\system32\vssvc.exe
C:\Windows\system32\vssvc.exe
1⤵
- Suspicious use of AdjustPrivilegeToken
PID:4448

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Command and Scripting Interpreter

1

T1059

PowerShell

1

T1059.001

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Persistence

Boot or Logon Autostart Execution

1

T1547

Registry Run Keys / Startup Folder

1

T1547.001

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Privilege Escalation

Boot or Logon Autostart Execution

1

T1547

Registry Run Keys / Startup Folder

1

T1547.001

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Defense Evasion

Modify Registry

1

T1112

Credential Access

Discovery

Query Registry

2

T1012

System Information Discovery

2

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_h1ltqy2k.vi1.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
C:\Users\Admin\AppData\Local\Temp\tmpCDDF.tmp.bat

Filesize
160B

MD5
3364888bf615e0f00997a6b00e600afe

SHA1
3bc1fa081b82bc3ce27a868a94a6f1bb4739e7f6

SHA256
af29acc4e89fc511b05bb6cace778e1bce2c3847e56e08b0ece0902d058d6b4d

SHA512
b1832b1cb1abfa64c38aacbf7f10228eb1d95382e9b13d4e5fb527eb1e02ee0e5caafc4ed888ff439059e8fede73630ce77304b915f9a43693567d826e1b32d5

Download Submit
C:\Users\Admin\SystemUser.exe\$77SystemUser.exe.exe

Filesize
42KB

MD5
953679a46f8bada4aea3c89e2026176a

SHA1
b78419d85a443d21fdd3bd6673c6c0b407f615da

SHA256
4008b0c3754f16bdf1365b0f894e48c82ccf5f8a656592fab4db899e11b73051

SHA512
4aabe38b1c404c4d61b08b4126bf509dc81cf50131db2c1061452cd795cc6c1f05055b03f8cadf99aa2b76f0f5c36fc3babe0cbb0a9d978a38fb71ca5f7ecd96

Download Submit
memory/1604-23-0x000001F6A8AE0000-0x000001F6A8B02000-memory.dmp

Filesize
136KB

Download
memory/2356-0-0x00007FFCD9873000-0x00007FFCD9875000-memory.dmp

Filesize
8KB

Download
memory/2356-1-0x0000000000AA0000-0x0000000000AB0000-memory.dmp

Filesize
64KB

Download
memory/2356-2-0x00007FFCD9870000-0x00007FFCDA331000-memory.dmp

Filesize
10.8MB

Download
memory/2356-3-0x00007FFCD9873000-0x00007FFCD9875000-memory.dmp

Filesize
8KB

Download
memory/2356-4-0x00007FFCD9870000-0x00007FFCDA331000-memory.dmp

Filesize
10.8MB

Download
memory/2356-10-0x00007FFCD9870000-0x00007FFCDA331000-memory.dmp

Filesize
10.8MB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads