xworm | c351ff303cfa1788ffb81e64a468871cb243a406d5c8fa2f6ddebba52c5198c0

General

Target

Chrome.exe
Size

173KB
MD5

3c7921e1847c67e0ea2e405dc6d39cd5
SHA1

3c8307af1999b5c404208a6f99feda968f51e9e7
SHA256

c351ff303cfa1788ffb81e64a468871cb243a406d5c8fa2f6ddebba52c5198c0
SHA512

685a3a564e78383a44aaaca72302b2c07e260800f9dd7279812102eb759932d33898b575243fd9c0169b80901ceb63b0bce592b65eae2639268f74c136c23bd2
SSDEEP

3072:WhNXZCckbL38bKROG7/4NpVq8BxFRzaqF+o2GQJ7/JzqVfGv8:ipCPb78OgVqwlL

Score

10^/10

xworm execution persistence rat trojan

Malware Config

Extracted

Family

xworm

Attributes

Install_directory
%Userprofile%
install_file
USB.exe
pastebin_url
https://pastebin.com/raw/sr6XiLTF

Signatures

Detect Xworm Payload 2 IoCs

resource	yara_rule
behavioral1/memory/228-1-0x0000000000270000-0x00000000002A2000-memory.dmp	family_xworm
behavioral1/files/0x00110000000240ab-58.dat	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
5012	powershell.exe
5276	powershell.exe
3620	powershell.exe
4612	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-1-5-21-3342763580-2723508992-2885672917-1000\Control Panel\International\Geo\Nation	Chrome.exe

Drops startup file 2 IoCs

description	ioc	Process
File created	C:\Users\Admin\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup\RtkAudUService64.lnk	Chrome.exe
File opened for modification	C:\Users\Admin\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup\RtkAudUService64.lnk	Chrome.exe

Executes dropped EXE 2 IoCs

pid	Process
5936	RtkAudUService64
4036	RtkAudUService64

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-1-5-21-3342763580-2723508992-2885672917-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\RtkAudUService64 = "C:\\Users\\Admin\\RtkAudUService64"	Chrome.exe

Legitimate hosting services abused for malware hosting/C2 1 TTPs 2 IoCs

Web Service

T1102

flow	ioc
30	pastebin.com
29	pastebin.com

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

System Information Discovery
T1082

Scheduled Task/Job: Scheduled Task 1 TTPs 1 IoCs

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

persistence execution

Scheduled Task

T1053.005

pid	Process
3816	schtasks.exe

Suspicious behavior: EnumeratesProcesses 8 IoCs

pid	Process
4612	powershell.exe
4612	powershell.exe
5012	powershell.exe
5012	powershell.exe
5276	powershell.exe
5276	powershell.exe
3620	powershell.exe
3620	powershell.exe

Suspicious use of AdjustPrivilegeToken 8 IoCs

description	pid	Process
Token: SeDebugPrivilege	228	Chrome.exe
Token: SeDebugPrivilege	4612	powershell.exe
Token: SeDebugPrivilege	5012	powershell.exe
Token: SeDebugPrivilege	5276	powershell.exe
Token: SeDebugPrivilege	3620	powershell.exe
Token: SeDebugPrivilege	228	Chrome.exe
Token: SeDebugPrivilege	5936	RtkAudUService64
Token: SeDebugPrivilege	4036	RtkAudUService64

Suspicious use of WriteProcessMemory 10 IoCs

description	pid	Process	procid_target
PID 228 wrote to memory of 4612	228	Chrome.exe	93
PID 228 wrote to memory of 4612	228	Chrome.exe	93
PID 228 wrote to memory of 5012	228	Chrome.exe	96
PID 228 wrote to memory of 5012	228	Chrome.exe	96
PID 228 wrote to memory of 5276	228	Chrome.exe	98
PID 228 wrote to memory of 5276	228	Chrome.exe	98
PID 228 wrote to memory of 3620	228	Chrome.exe	101
PID 228 wrote to memory of 3620	228	Chrome.exe	101
PID 228 wrote to memory of 3816	228	Chrome.exe	103
PID 228 wrote to memory of 3816	228	Chrome.exe	103

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

C:\Users\Admin\AppData\Local\Temp\Chrome.exe
"C:\Users\Admin\AppData\Local\Temp\Chrome.exe"
1⤵
- Checks computer location settings
- Drops startup file
- Adds Run key to start application
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:228
- 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\Chrome.exe'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:4612
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass Add-MpPreference -ExclusionProcess 'Chrome.exe'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:5012
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass Add-MpPreference -ExclusionPath 'C:\Users\Admin\RtkAudUService64'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:5276
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass Add-MpPreference -ExclusionProcess 'RtkAudUService64'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:3620
- C:\Windows\System32\schtasks.exe
  "C:\Windows\System32\schtasks.exe" /create /f /RL HIGHEST /sc minute /mo 1 /tn "RtkAudUService64" /tr "C:\Users\Admin\RtkAudUService64"
  2⤵
  - Scheduled Task/Job: Scheduled Task
  PID:3816

C:\Windows\system32\cmd.exe
C:\Windows\system32\cmd.exe /c C:\Users\Admin\RtkAudUService64
1⤵
PID:5496

C:\Users\Admin\RtkAudUService64
C:\Users\Admin\RtkAudUService64
1⤵
- Executes dropped EXE
- Suspicious use of AdjustPrivilegeToken
PID:5936

C:\Users\Admin\RtkAudUService64
C:\Users\Admin\RtkAudUService64
1⤵
- Executes dropped EXE
- Suspicious use of AdjustPrivilegeToken
PID:4036

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

Web Service

1

T1102

Exfiltration

Impact

Replay Monitor

Loading Replay Monitor...

Downloads

C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0\UsageLogs\RtkAudUService64.log

Filesize
654B

MD5
2ff39f6c7249774be85fd60a8f9a245e

SHA1
684ff36b31aedc1e587c8496c02722c6698c1c4e

SHA256
e1b91642d85d98124a6a31f710e137ab7fd90dec30e74a05ab7fcf3b7887dced

SHA512
1d7e8b92ef4afd463d62cfa7e8b9d1799db5bf2a263d3cd7840df2e0a1323d24eb595b5f8eb615c6cb15f9e3a7b4fc99f8dd6a3d34479222e966ec708998aed1

Download Submit
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
ffaa33c7940b1713a06a430414e2fed0

SHA1
b1ade7d02b641ac9c382fad82cb1d31362fafb91

SHA256
a9c2268a32d4b53421c510878be105729a41bb03d01622456369d322e3e35c5e

SHA512
61913fe437de06bae8a99a02f3ff35f483d06ddd9593c16f9bb652dde94930ff47f1a07765b2d78ac5108abb65837a66444dc7ff9691ba9c9ceaf85f0ae73f4d

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

Filesize
944B

MD5
1099dc40baabde4be41cc1faf6353f7d

SHA1
345705c6b9adc64389b6d142e7484d0cdd4f2bd0

SHA256
6cec99d44ed65e73240a96691f299a41e944a9c8f59c543df3ecd73d95c8bf40

SHA512
6315f1089cc8139531acc422741290c84a60841a65a8cc9844cd907c96694d33d164120c36f460a0bef03e67e2a60c33f9c968ac41edf3dd82cab015e00e74a1

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

Filesize
944B

MD5
15dde0683cd1ca19785d7262f554ba93

SHA1
d039c577e438546d10ac64837b05da480d06bf69

SHA256
d6fa39eab7ee36f44dc3f9f2839d098433db95c1eba924e4bcf4e5c0d268d961

SHA512
57c0e1b87bc1c136f0d39f3ce64bb8f8274a0491e4ca6e45e5c7f9070aa9d9370c6f590ce37cd600b252df2638d870205249a514c43245ca7ed49017024a4672

Download Submit
C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_xul1cvst.vk4.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
C:\Users\Admin\RtkAudUService64

Filesize
173KB

MD5
3c7921e1847c67e0ea2e405dc6d39cd5

SHA1
3c8307af1999b5c404208a6f99feda968f51e9e7

SHA256
c351ff303cfa1788ffb81e64a468871cb243a406d5c8fa2f6ddebba52c5198c0

SHA512
685a3a564e78383a44aaaca72302b2c07e260800f9dd7279812102eb759932d33898b575243fd9c0169b80901ceb63b0bce592b65eae2639268f74c136c23bd2

Download Submit
memory/228-55-0x00007FFADE5C3000-0x00007FFADE5C5000-memory.dmp

Filesize
8KB

Download
memory/228-0-0x00007FFADE5C3000-0x00007FFADE5C5000-memory.dmp

Filesize
8KB

Download
memory/228-56-0x00007FFADE5C0000-0x00007FFADF081000-memory.dmp

Filesize
10.8MB

Download
memory/228-57-0x00007FFADE5C0000-0x00007FFADF081000-memory.dmp

Filesize
10.8MB

Download
memory/228-1-0x0000000000270000-0x00000000002A2000-memory.dmp

Filesize
200KB

Download
memory/4612-17-0x00007FFADE5C0000-0x00007FFADF081000-memory.dmp

Filesize
10.8MB

Download
memory/4612-14-0x00007FFADE5C0000-0x00007FFADF081000-memory.dmp

Filesize
10.8MB

Download
memory/4612-13-0x00007FFADE5C0000-0x00007FFADF081000-memory.dmp

Filesize
10.8MB

Download
memory/4612-12-0x00007FFADE5C0000-0x00007FFADF081000-memory.dmp

Filesize
10.8MB

Download
memory/4612-2-0x000002225EB30000-0x000002225EB52000-memory.dmp

Filesize
136KB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

Replay Monitor

Loading Replay Monitor...

Downloads