xworm | 3ac3efee88adab86a250a53dd9448453fcc4223662f5c6c21453606b6eb91b77

General

Target

Realtek HD Audio Universal Service.exe
Size

53KB
MD5

ce3e5f8613ea049b651549eba3e3aa28
SHA1

1197375be314ae5a69f3b742f0f539b881aca09a
SHA256

9385116a4a3874548ffa027f4cd448d860ef8dc13fc687ce87790a01ede8e73a
SHA512

ab1428177b5ec71447003ac01f5f99d9c7f2af634f17ef53d6f6be196714faac856b0bc3f62b6fad9975dad970ec247d35f56615c62b9ad483426f4ecaae71c2
SSDEEP

768:/63AQe9cfNbv5s7Xol68y+JN/Db3dLPowu7aR6vaTOouhIZqklm:/WAQbdvoolZJ9b3dLPoCR68OnkZ8

Score

10^/10

xworm execution persistence rat trojan

Malware Config

Extracted

Family

xworm

C2

147.185.221.23:58112

Attributes

Install_directory
%AppData%
install_file
Realtek HD Audio Universal Service.exe

Signatures

Detect Xworm Payload 1 IoCs

resource	yara_rule
behavioral4/memory/3736-1-0x0000000000720000-0x0000000000734000-memory.dmp	family_xworm

Xworm
Xworm is a remote access trojan written in C#.
trojan rat xworm
Xworm family
xworm

Command and Scripting Interpreter: PowerShell 1 TTPs 4 IoCs

Run Powershell to modify Windows Defender settings to add exclusions for file extensions, paths, and processes.

execution

PowerShell

T1059.001

pid	Process
2180	powershell.exe
464	powershell.exe
2388	powershell.exe
4412	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-1-5-21-3350944739-639801879-157714471-1000\Control Panel\International\Geo\Nation	Realtek HD Audio Universal Service.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-1-5-21-3350944739-639801879-157714471-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\Realtek HD Audio Universal Service = "C:\\Users\\Admin\\AppData\\Roaming\\Realtek HD Audio Universal Service.exe"	Realtek HD Audio Universal Service.exe

Looks up external IP address via web service 1 IoCs

Uses a legitimate IP lookup service to find the infected system's external IP.

flow	ioc
15	ip-api.com

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

System Information Discovery
T1082

Suspicious behavior: EnumeratesProcesses 9 IoCs

pid	Process
2388	powershell.exe
2388	powershell.exe
4412	powershell.exe
4412	powershell.exe
2180	powershell.exe
2180	powershell.exe
464	powershell.exe
464	powershell.exe
3736	Realtek HD Audio Universal Service.exe

Suspicious use of AdjustPrivilegeToken 5 IoCs

description	pid	Process
Token: SeDebugPrivilege	3736	Realtek HD Audio Universal Service.exe
Token: SeDebugPrivilege	2388	powershell.exe
Token: SeDebugPrivilege	4412	powershell.exe
Token: SeDebugPrivilege	2180	powershell.exe
Token: SeDebugPrivilege	464	powershell.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
3736	Realtek HD Audio Universal Service.exe

Suspicious use of WriteProcessMemory 8 IoCs

description	pid	Process	procid_target
PID 3736 wrote to memory of 2388	3736	Realtek HD Audio Universal Service.exe	91
PID 3736 wrote to memory of 2388	3736	Realtek HD Audio Universal Service.exe	91
PID 3736 wrote to memory of 4412	3736	Realtek HD Audio Universal Service.exe	93
PID 3736 wrote to memory of 4412	3736	Realtek HD Audio Universal Service.exe	93
PID 3736 wrote to memory of 2180	3736	Realtek HD Audio Universal Service.exe	95
PID 3736 wrote to memory of 2180	3736	Realtek HD Audio Universal Service.exe	95
PID 3736 wrote to memory of 464	3736	Realtek HD Audio Universal Service.exe	99
PID 3736 wrote to memory of 464	3736	Realtek HD Audio Universal Service.exe	99

C:\Users\Admin\AppData\Local\Temp\Realtek HD Audio Universal Service.exe
"C:\Users\Admin\AppData\Local\Temp\Realtek HD Audio Universal Service.exe"
1⤵
- Checks computer location settings
- Adds Run key to start application
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:3736
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass Add-MpPreference -ExclusionPath 'C:\Users\Admin\AppData\Local\Temp\Realtek HD Audio Universal Service.exe'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:2388
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass Add-MpPreference -ExclusionProcess 'Realtek HD Audio Universal Service.exe'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:4412
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass Add-MpPreference -ExclusionPath 'C:\Users\Admin\AppData\Roaming\Realtek HD Audio Universal Service.exe'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:2180
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass Add-MpPreference -ExclusionProcess 'Realtek HD Audio Universal Service.exe'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:464

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Command and Scripting Interpreter

1

T1059

PowerShell

1

T1059.001

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

System Information Discovery

2

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0\UsageLogs\powershell.exe.log

Filesize
2KB

MD5
d85ba6ff808d9e5444a4b369f5bc2730

SHA1
31aa9d96590fff6981b315e0b391b575e4c0804a

SHA256
84739c608a73509419748e4e20e6cc4e1846056c3fe1929a8300d5a1a488202f

SHA512
8c414eb55b45212af385accc16d9d562adba2123583ce70d22b91161fe878683845512a78f04dedd4ea98ed9b174dbfa98cf696370598ad8e6fbd1e714f1f249

Download Submit
C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

Filesize
944B

MD5
77d622bb1a5b250869a3238b9bc1402b

SHA1
d47f4003c2554b9dfc4c16f22460b331886b191b

SHA256
f97ff12a8abf4bf88bb6497bd2ac2da12628c8847a8ba5a9026bdbb76507cdfb

SHA512
d6789b5499f23c9035375a102271e17a8a82e57d6f5312fa24242e08a83efdeb8becb7622f55c4cf1b89c7d864b445df11f4d994cf7e2f87a900535bcca12fd9

Download Submit
C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

Filesize
944B

MD5
dd1d0b083fedf44b482a028fb70b96e8

SHA1
dc9c027937c9f6d52268a1504cbae42a39c8d36a

SHA256
cab7944d29e0501dc0db904ac460ca7a87700e0ec7eb62298b7b97cbf40c424c

SHA512
96bec38bfda176292ae65dcf735103e7888baa212038737c1d1e215fcb76e4c0355e4a827a1934303e7aecae91012fa412f13e38f382b732758bae985cc67973

Download Submit
C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

Filesize
944B

MD5
ee9f1be5d4d351a5c376b370adcf0eea

SHA1
1779cecfb13c6a2f0f2813ae65d0d91ebdcf5583

SHA256
70600f0f93bca5f0548bfe5503513caadda31cbcd14dc007824b0925a8626e4b

SHA512
fda7345f64a6352e99bb3f5d94e58751a71d45a27147f60da32d12ff0307dbe416f482f1b9950e52ce63cbb5f0e5c1647f72dbb7a05c5419ccd8b7980ea86754

Download Submit
C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_eu3oxvzj.v4n.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
memory/2388-3-0x00007FF97C100000-0x00007FF97CBC1000-memory.dmp

Filesize
10.8MB

Download
memory/2388-14-0x00007FF97C100000-0x00007FF97CBC1000-memory.dmp

Filesize
10.8MB

Download
memory/2388-15-0x00007FF97C100000-0x00007FF97CBC1000-memory.dmp

Filesize
10.8MB

Download
memory/2388-18-0x00007FF97C100000-0x00007FF97CBC1000-memory.dmp

Filesize
10.8MB

Download
memory/2388-13-0x0000028FA9310000-0x0000028FA9332000-memory.dmp

Filesize
136KB

Download
memory/3736-0-0x00007FF97C103000-0x00007FF97C105000-memory.dmp

Filesize
8KB

Download
memory/3736-2-0x00007FF97C100000-0x00007FF97CBC1000-memory.dmp

Filesize
10.8MB

Download
memory/3736-1-0x0000000000720000-0x0000000000734000-memory.dmp

Filesize
80KB

Download
memory/3736-54-0x00007FF97C103000-0x00007FF97C105000-memory.dmp

Filesize
8KB

Download
memory/3736-55-0x00007FF97C100000-0x00007FF97CBC1000-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