quasar | 58f7dda2165a44ddad0d441ba356a0626d1ad619d766a58008320ec5936cdb94

General

Target

Client-built.exe
Size

3.1MB
MD5

2df7f55c626ea8077ef2cc5ffd32dc38
SHA1

93131a8d6128ea827f1f31ada4391f94bbc1dd06
SHA256

58f7dda2165a44ddad0d441ba356a0626d1ad619d766a58008320ec5936cdb94
SHA512

362bfea6ae2127df5da06904407286c0ed49846ec230ae149a46a4cdcdb101987963a406427283d409957427bdc57a77c3ac90f567b3d00ad561f025f10912cc
SSDEEP

49152:ZvZI22SsaNYfdPBldt698dBcjHVi/2BxmgoGd5UTHHB72eh2NT:Zva22SsaNYfdPBldt6+dBcjHU/O

Score

10^/10

quasar office04 discovery spyware trojan

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

Office04

C2

85.209.133.15:111

Mutex

95ddd19c-037b-4e62-8c64-298b31d663b8

Attributes

encryption_key
43DE31297B50FED5B1E6867AE89B621C68EF71E2
install_name
Client.exe
log_directory
Logs
reconnect_delay
3000
startup_key
Quasar Client Startup
subdirectory
SubDir

Signatures

Quasar RAT
Quasar is an open source Remote Access Tool.
trojan spyware quasar
Quasar family
quasar

Quasar payload 1 IoCs

resource	yara_rule
behavioral2/memory/4232-1-0x0000000000C70000-0x0000000000F94000-memory.dmp	family_quasar

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-1-5-21-3226857575-536881564-1522996248-1000\Control Panel\International\Geo\Nation	Client-built.exe

Executes dropped EXE 1 IoCs

pid	Process
1836	kLreEzgtKab7.exe

Drops file in System32 directory 2 IoCs

description	ioc	Process
File opened for modification	C:\Windows\system32\config\systemprofile\AppData\Local\Microsoft\Windows\1033\StructuredQuerySchema.bin	LogonUI.exe
File opened for modification	C:\Windows\system32\config\systemprofile\AppData\Local\Microsoft\Windows\Caches\cversions.3.db	LogonUI.exe

Drops file in Windows directory 1 IoCs

description	ioc	Process
File created	C:\Windows\rescache\_merged\2229298842\3223637799.pri	LogonUI.exe

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

System Information Discovery
T1082

System Location Discovery: System Language Discovery 1 TTPs 1 IoCs

Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

discovery

System Language Discovery

T1614.001

description	ioc	Process
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	kLreEzgtKab7.exe

Modifies data under HKEY_USERS 15 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\Accent	LogonUI.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Themes\History	LogonUI.exe
Key created	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM	LogonUI.exe
Set value (int)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\AccentColor = "4292311040"	LogonUI.exe
Set value (int)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationBlurBalance = "1"	LogonUI.exe
Set value (int)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\EnableWindowColorization = "108"	LogonUI.exe
Set value (int)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Themes\History\AutoColor = "0"	LogonUI.exe
Set value (int)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\Accent\StartColorMenu = "4288567808"	LogonUI.exe
Set value (int)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\Accent\AccentColorMenu = "4292311040"	LogonUI.exe
Set value (int)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationGlassAttribute = "1"	LogonUI.exe
Set value (data)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\Accent\AccentPalette = a6d8ff0076b9ed00429ce3000078d700005a9e000042750000264200f7630c00	LogonUI.exe
Set value (int)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationColor = "3288365271"	LogonUI.exe
Set value (int)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationColorBalance = "89"	LogonUI.exe
Set value (int)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationAfterglow = "3288365271"	LogonUI.exe
Set value (int)	\REGISTRY\USER\.DEFAULT\Software\Microsoft\Windows\DWM\ColorizationAfterglowBalance = "10"	LogonUI.exe

Suspicious use of AdjustPrivilegeToken 8 IoCs

description	pid	Process
Token: SeDebugPrivilege	4232	Client-built.exe
Token: SeDebugPrivilege	1836	kLreEzgtKab7.exe
Token: 33	4896	AUDIODG.EXE
Token: SeIncBasePriorityPrivilege	4896	AUDIODG.EXE
Token: SeShutdownPrivilege	1896	shutdown.exe
Token: SeRemoteShutdownPrivilege	1896	shutdown.exe
Token: SeShutdownPrivilege	1580	LogonUI.exe
Token: SeCreatePagefilePrivilege	1580	LogonUI.exe

Suspicious use of FindShellTrayWindow 4 IoCs

pid	Process
4232	Client-built.exe
4232	Client-built.exe
4232	Client-built.exe
4232	Client-built.exe

Suspicious use of SendNotifyMessage 4 IoCs

pid	Process
4232	Client-built.exe
4232	Client-built.exe
4232	Client-built.exe
4232	Client-built.exe

Suspicious use of SetWindowsHookEx 2 IoCs

pid	Process
1580	LogonUI.exe
1580	LogonUI.exe

Suspicious use of WriteProcessMemory 5 IoCs

description	pid	Process	procid_target
PID 4232 wrote to memory of 1836	4232	Client-built.exe	90
PID 4232 wrote to memory of 1836	4232	Client-built.exe	90
PID 4232 wrote to memory of 1836	4232	Client-built.exe	90
PID 4232 wrote to memory of 1896	4232	Client-built.exe	92
PID 4232 wrote to memory of 1896	4232	Client-built.exe	92

C:\Users\Admin\AppData\Local\Temp\Client-built.exe
"C:\Users\Admin\AppData\Local\Temp\Client-built.exe"
1⤵
- Checks computer location settings
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of FindShellTrayWindow
- Suspicious use of SendNotifyMessage
- Suspicious use of WriteProcessMemory
PID:4232
- C:\Users\Admin\AppData\Local\Temp\kLreEzgtKab7.exe
  "C:\Users\Admin\AppData\Local\Temp\kLreEzgtKab7.exe"
  2⤵
  - Executes dropped EXE
  - System Location Discovery: System Language Discovery
  - Suspicious use of AdjustPrivilegeToken
  PID:1836
- C:\Windows\System32\shutdown.exe
  "C:\Windows\System32\shutdown.exe" /s /t 0
  2⤵
  - Suspicious use of AdjustPrivilegeToken
  PID:1896

C:\Windows\system32\AUDIODG.EXE
C:\Windows\system32\AUDIODG.EXE 0x4f8 0x308
1⤵
- Suspicious use of AdjustPrivilegeToken
PID:4896

C:\Windows\system32\LogonUI.exe
"LogonUI.exe" /flags:0x4 /state0:0xa3a1d055 /state1:0x41c64e6d
1⤵
- Drops file in System32 directory
- Drops file in Windows directory
- Modifies data under HKEY_USERS
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of SetWindowsHookEx
PID:1580

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Discovery

Query Registry

1

T1012

System Information Discovery

2

T1082

System Location Discovery

1

T1614

System Language Discovery

1

T1614.001

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\Users\Admin\AppData\Local\Temp\kLreEzgtKab7.exe

Filesize
854KB

MD5
5fdbb633c00c6ae9a7f850236e0eb4c4

SHA1
3779b3e58e64b7045abd0ab8764918285b2e24d4

SHA256
ec2fc127825e04f42d45c436cf7ee484aac78bdb94b4ea4d077d6b7c88379037

SHA512
710ea49f9a1aea061c5c887d6025da86be6ce0cbd40a42c71c8f1c78438ffdbbbe34ed4b8853f1e3468e3ae3e629ef147b271dbceac0b83542ece08dfcd12e61

Download Submit
memory/1836-32-0x0000000074D40000-0x00000000754F1000-memory.dmp

Filesize
7.7MB

Download
memory/1836-31-0x0000000074D4E000-0x0000000074D4F000-memory.dmp

Filesize
4KB

Download
memory/1836-29-0x0000000004FB0000-0x0000000004FBA000-memory.dmp

Filesize
40KB

Download
memory/1836-30-0x0000000074D40000-0x00000000754F1000-memory.dmp

Filesize
7.7MB

Download
memory/1836-28-0x0000000005020000-0x00000000050B2000-memory.dmp

Filesize
584KB

Download
memory/1836-27-0x00000000055D0000-0x0000000005B76000-memory.dmp

Filesize
5.6MB

Download
memory/1836-26-0x0000000000500000-0x00000000005DC000-memory.dmp

Filesize
880KB

Download
memory/1836-25-0x0000000074D4E000-0x0000000074D4F000-memory.dmp

Filesize
4KB

Download
memory/4232-4-0x000000001D0A0000-0x000000001D152000-memory.dmp

Filesize
712KB

Download
memory/4232-10-0x00007FF86DFC0000-0x00007FF86EA82000-memory.dmp

Filesize
10.8MB

Download
memory/4232-9-0x00007FF86DFC3000-0x00007FF86DFC5000-memory.dmp

Filesize
8KB

Download
memory/4232-8-0x000000001D040000-0x000000001D07C000-memory.dmp

Filesize
240KB

Download
memory/4232-7-0x000000001CFE0000-0x000000001CFF2000-memory.dmp

Filesize
72KB

Download
memory/4232-0-0x00007FF86DFC3000-0x00007FF86DFC5000-memory.dmp

Filesize
8KB

Download
memory/4232-3-0x000000001CF90000-0x000000001CFE0000-memory.dmp

Filesize
320KB

Download
memory/4232-2-0x00007FF86DFC0000-0x00007FF86EA82000-memory.dmp

Filesize
10.8MB

Download
memory/4232-1-0x0000000000C70000-0x0000000000F94000-memory.dmp

Filesize
3.1MB

Download
memory/4232-35-0x00007FF86DFC0000-0x00007FF86EA82000-memory.dmp

Filesize
10.8MB

Download

Analysis

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