xworm | 9e2cc1e98ba3672218c8fbdeb5c8831c340a25c4b425ee32bf45527577c8eb2c

General

Target

Realtek HD Audio Universal Service.exe
Size

40KB
MD5

876020bf5050a2b498b45cb65d89f067
SHA1

7f7ace329e3c77e14fc5bb11d1797e5f61f96859
SHA256

9e2cc1e98ba3672218c8fbdeb5c8831c340a25c4b425ee32bf45527577c8eb2c
SHA512

f168fe3bb22c1947036418737845c9200c5642fec69d24a982d47d2c0da9502e8e8e86268fae5c39f28ab8267fc4cb2644a9e27a4f8b898dfafd4c5b801fd7c0
SSDEEP

768:MBj78fx6MooenBjJfDUbtRFH9OKl6BOMhXL05jh:o78p6MLeBjJfIbDFH93l6BOMFkjh

Score

10^/10

xworm execution rat trojan

Malware Config

Extracted

Family

xworm

Version

5.0

C2

147.185.221.23:57069

Mutex

lW9cEvIRnaJBDeUt

Attributes

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

aes.plain

Signatures

Detect Xworm Payload 1 IoCs

resource	yara_rule
behavioral2/memory/2864-1-0x0000000000620000-0x0000000000630000-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
2840	powershell.exe
1616	powershell.exe
3284	powershell.exe
1056	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-1-5-21-3227495264-2217614367-4027411560-1000\Control Panel\International\Geo\Nation	Realtek HD Audio Universal Service.exe

Drops startup file 2 IoCs

description	ioc	Process
File created	C:\Users\Admin\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup\Realtek HD Audio Universal Service.lnk	Realtek HD Audio Universal Service.exe
File opened for modification	C:\Users\Admin\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup\Realtek HD Audio Universal Service.lnk	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
3	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
2840	powershell.exe
2840	powershell.exe
1616	powershell.exe
1616	powershell.exe
3284	powershell.exe
3284	powershell.exe
1056	powershell.exe
1056	powershell.exe
2864	Realtek HD Audio Universal Service.exe

Suspicious use of AdjustPrivilegeToken 5 IoCs

description	pid	Process
Token: SeDebugPrivilege	2864	Realtek HD Audio Universal Service.exe
Token: SeDebugPrivilege	2840	powershell.exe
Token: SeDebugPrivilege	1616	powershell.exe
Token: SeDebugPrivilege	3284	powershell.exe
Token: SeDebugPrivilege	1056	powershell.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
2864	Realtek HD Audio Universal Service.exe

Suspicious use of WriteProcessMemory 8 IoCs

description	pid	Process	procid_target
PID 2864 wrote to memory of 2840	2864	Realtek HD Audio Universal Service.exe	88
PID 2864 wrote to memory of 2840	2864	Realtek HD Audio Universal Service.exe	88
PID 2864 wrote to memory of 1616	2864	Realtek HD Audio Universal Service.exe	90
PID 2864 wrote to memory of 1616	2864	Realtek HD Audio Universal Service.exe	90
PID 2864 wrote to memory of 3284	2864	Realtek HD Audio Universal Service.exe	92
PID 2864 wrote to memory of 3284	2864	Realtek HD Audio Universal Service.exe	92
PID 2864 wrote to memory of 1056	2864	Realtek HD Audio Universal Service.exe	94
PID 2864 wrote to memory of 1056	2864	Realtek HD Audio Universal Service.exe	94

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
- Drops startup file
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:2864
- 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:2840
- 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:1616
- 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\Realtek HD Audio Universal Service.exe'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:3284
- 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:1056

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Command and Scripting Interpreter

1

T1059

PowerShell

1

T1059.001

Persistence

Privilege Escalation

Defense Evasion

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
2e907f77659a6601fcc408274894da2e

SHA1
9f5b72abef1cd7145bf37547cdb1b9254b4efe9d

SHA256
385da35673330e21ac02545220552fe301fe54dedefbdafc097ac4342a295233

SHA512
34fa0fff24f6550f55f828541aaefe5d75c86f8f0842d54b50065e9746f9662bb7209c74c9a9571540b9855bb3851f01db613190024e89b198d485bb5dc07721

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

Filesize
944B

MD5
d2cfcaec8842041e069da07ebdf9ad1f

SHA1
000d391e61cafe523f535e3b206835bbfc96299b

SHA256
d9c1757a17a04213e3ea02d33192563cbbd1ac94e33228278dc3577c589a0fd3

SHA512
41b337225bd920fa14b0b7045b6050c60c97cb2e73937993bfcac780dfc40ec5cc80bc770f74ef9bef6cbc30df446355b6c63a5ce0918bcd21a382f32fc31546

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

Filesize
944B

MD5
cc19bcff372d20459d3651ba8aef50e7

SHA1
3c6f1d4cdd647864fb97a16b1aefba67fcee11f7

SHA256
366473e774d8976c7fd4dc582220666fb61a4feb3f7c95e69b2a68ad9e446ec9

SHA512
a0e360ca4b6e874fd44612bf4b17f3722c0619da4f6bade12a62efadae88c2d33460114eaafa2bc3fb1cef5bea07e745b8bee24f15d0cacaff5f4a521b225080

Download Submit
C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_f2vn4btn.f1r.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
memory/2840-19-0x00007FFBFD200000-0x00007FFBFDCC1000-memory.dmp

Filesize
10.8MB

Download
memory/2840-14-0x0000021FBBDF0000-0x0000021FBBE12000-memory.dmp

Filesize
136KB

Download
memory/2840-15-0x00007FFBFD200000-0x00007FFBFDCC1000-memory.dmp

Filesize
10.8MB

Download
memory/2840-16-0x00007FFBFD200000-0x00007FFBFDCC1000-memory.dmp

Filesize
10.8MB

Download
memory/2864-0-0x00007FFBFD203000-0x00007FFBFD205000-memory.dmp

Filesize
8KB

Download
memory/2864-4-0x00007FFBFD200000-0x00007FFBFDCC1000-memory.dmp

Filesize
10.8MB

Download
memory/2864-3-0x00007FFBFD203000-0x00007FFBFD205000-memory.dmp

Filesize
8KB

Download
memory/2864-2-0x00007FFBFD200000-0x00007FFBFDCC1000-memory.dmp

Filesize
10.8MB

Download
memory/2864-1-0x0000000000620000-0x0000000000630000-memory.dmp

Filesize
64KB

Download

Analysis

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