xworm | feba3474a30f9b010741c34ee4773777fc329390418713ffef424b2eb9243a5f

General

Target

crss.exe
Size

40KB
MD5

3ab61ee8a81099edddf87af587420a10
SHA1

d6c0f6f60d13cc786cf7ac0df2c45b5dc47b945c
SHA256

feba3474a30f9b010741c34ee4773777fc329390418713ffef424b2eb9243a5f
SHA512

f43326c79ea8bd118fd90efc8c2c8306e02901727ffd7c6666b2a35820eb8799976007f4886a68a7f411509ad61dcf7ddf5a3630fa5342014ad5aa978818ff3f
SSDEEP

768:pNfPMSk3K/EzTb/008WuFZ4ZJF5PC9O9Fy68OMhi3/aV:nf05a/CTjp89IFc9Uc68OMsi

Score

10^/10

xworm execution rat trojan

Malware Config

Extracted

Family

xworm

Version

5.0

C2

154.197.69.165:7000

Mutex

jcTVbnlMjCEJAYCp

Attributes

Install_directory
%AppData%
install_file
crss.exe

aes.plain

Signatures

Detect Xworm Payload 1 IoCs

resource	yara_rule
behavioral2/memory/3408-1-0x0000000000580000-0x0000000000590000-memory.dmp	family_xworm

Xworm
Xworm is a remote access trojan written in C#.
trojan rat 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
2428	powershell.exe
2540	powershell.exe
4572	powershell.exe
3156	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-1-5-21-2412658365-3084825385-3340777666-1000\Control Panel\International\Geo\Nation	crss.exe

Drops startup file 2 IoCs

description	ioc	Process
File created	C:\Users\Admin\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup\crss.lnk	crss.exe
File opened for modification	C:\Users\Admin\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup\crss.lnk	crss.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
21	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
2428	powershell.exe
2428	powershell.exe
2540	powershell.exe
2540	powershell.exe
4572	powershell.exe
4572	powershell.exe
3156	powershell.exe
3156	powershell.exe
3408	crss.exe

Suspicious use of AdjustPrivilegeToken 6 IoCs

description	pid	Process
Token: SeDebugPrivilege	3408	crss.exe
Token: SeDebugPrivilege	2428	powershell.exe
Token: SeDebugPrivilege	2540	powershell.exe
Token: SeDebugPrivilege	4572	powershell.exe
Token: SeDebugPrivilege	3156	powershell.exe
Token: SeDebugPrivilege	3408	crss.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
3408	crss.exe

Suspicious use of WriteProcessMemory 8 IoCs

description	pid	Process	procid_target
PID 3408 wrote to memory of 2428	3408	crss.exe	92
PID 3408 wrote to memory of 2428	3408	crss.exe	92
PID 3408 wrote to memory of 2540	3408	crss.exe	95
PID 3408 wrote to memory of 2540	3408	crss.exe	95
PID 3408 wrote to memory of 4572	3408	crss.exe	97
PID 3408 wrote to memory of 4572	3408	crss.exe	97
PID 3408 wrote to memory of 3156	3408	crss.exe	99
PID 3408 wrote to memory of 3156	3408	crss.exe	99

C:\Users\Admin\AppData\Local\Temp\crss.exe
"C:\Users\Admin\AppData\Local\Temp\crss.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:3408
- 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\crss.exe'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:2428
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass Add-MpPreference -ExclusionProcess 'crss.exe'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:2540
- 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\crss.exe'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:4572
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass Add-MpPreference -ExclusionProcess 'crss.exe'
  2⤵
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:3156

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
293a5e452e148112857e22e746feff34

SHA1
7a5018bf98a3e38970809531288a7e3efb979532

SHA256
05e48657fb5340817f522c955b379cfb639977480af3ab1414682e9bf6616551

SHA512
7332f2b22f4ab64bb67c1a493f7cf2b378e311d5be6c6c99339210d4e9022c17f01a698333cd679a0776cca23460e28ec88c2ccfcf50c732ee218ef25ab19049

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

Filesize
944B

MD5
2117cf9865e42aacdfc8925e05fe4031

SHA1
f89be0d1409b864d85da2479dbcf4382b9a8e888

SHA256
97ed8e4e2f74329c27b63cc9b72b4af1cdc51c4dc014725b80b51da93b91192d

SHA512
83e12e1658ae4bf6b89edaa04e3e81492b9d25990745ab429ebf861915826512213ac9accc1323a5f3d71a821c07ff9010aa8772eb6b0bf6a93649b3ca112166

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

Filesize
944B

MD5
ef72c47dbfaae0b9b0d09f22ad4afe20

SHA1
5357f66ba69b89440b99d4273b74221670129338

SHA256
692ec20c7039170fb199510f0436181fd155e6b4516d4d1c9e1675adf99aaa7f

SHA512
7514b6bc8dc39fa618223300be27cd535dc35b18c66b4a089e2302e72b3e0cac06d88a989fa1296feb386b3cbe2084019df6430c7f895071b76e04ce559a30b4

Download Submit
C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_kbggd3vv.lhd.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
memory/2428-5-0x00000223CE8D0000-0x00000223CE8F2000-memory.dmp

Filesize
136KB

Download
memory/2428-17-0x00007FFAEF170000-0x00007FFAEFC31000-memory.dmp

Filesize
10.8MB

Download
memory/2428-4-0x00007FFAEF170000-0x00007FFAEFC31000-memory.dmp

Filesize
10.8MB

Download
memory/2428-3-0x00007FFAEF170000-0x00007FFAEFC31000-memory.dmp

Filesize
10.8MB

Download
memory/3408-0-0x00007FFAEF173000-0x00007FFAEF175000-memory.dmp

Filesize
8KB

Download
memory/3408-2-0x00007FFAEF170000-0x00007FFAEFC31000-memory.dmp

Filesize
10.8MB

Download
memory/3408-1-0x0000000000580000-0x0000000000590000-memory.dmp

Filesize
64KB

Download
memory/3408-56-0x00007FFAEF173000-0x00007FFAEF175000-memory.dmp

Filesize
8KB

Download
memory/3408-57-0x00007FFAEF170000-0x00007FFAEFC31000-memory.dmp

Filesize
10.8MB

Download

Analysis

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