quasar | 1b701daded4124260a49040d83dec15c627b8e4a1a04dc378aae7fecfca3abf3

General

Target

CritScript.exe
Size

3.2MB
MD5

c28dc010fc5198442496bc07dd50cd5d
SHA1

0f90a005815c2700a65ea85ae86f13a182cc11e6
SHA256

1b701daded4124260a49040d83dec15c627b8e4a1a04dc378aae7fecfca3abf3
SHA512

7c94bafa48db045a864a778a010a7d1d03204828bd103a86c1267732a51260b0e689a799cc7e95410ceedd1254fb91aa3f19f62efa3e41e40be645862a4e07e2
SSDEEP

49152:IuvyI22SsaNYfdPBldt698dBcjH7BhSR1J/xoGdoTHHB72eh2NT:Iuvf22SsaNYfdPBldt6+dBcjH7BhSb

Score

10^/10

quasar ddns discovery spyware trojan

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

DDNS

C2

193.161.193.99:32471

Mutex

807f3187-d087-4fff-beff-e73293a32af8

Attributes

encryption_key
81A0C14D4C705B3C678E573C849DE7F6A3671A8B
install_name
jusched.exe
log_directory
CachedLogs
reconnect_delay
3000
startup_key
Java Update Scheduler
subdirectory
Java

Signatures

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

Quasar payload 2 IoCs

resource	yara_rule
behavioral2/files/0x0008000000023c92-4.dat	family_quasar
behavioral2/memory/2796-14-0x00000000008C0000-0x0000000000BE4000-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-1-5-21-3756129449-3121373848-4276368241-1000\Control Panel\International\Geo\Nation	CritScript.exe

Executes dropped EXE 2 IoCs

pid	Process
2796	JUSCHED.EXE
2140	jusched.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	CritScript.exe

Modifies registry class 2 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-3756129449-3121373848-4276368241-1000_Classes\Local Settings	CritScript.exe
Key created	\REGISTRY\USER\S-1-5-21-3756129449-3121373848-4276368241-1000_Classes\Local Settings	OpenWith.exe

Scheduled Task/Job: Scheduled Task 1 TTPs 2 IoCs

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

persistence execution

Scheduled Task

T1053.005

pid	Process
3908	schtasks.exe
2688	schtasks.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	2796	JUSCHED.EXE
Token: SeDebugPrivilege	2140	jusched.exe

Suspicious use of SetWindowsHookEx 2 IoCs

pid	Process
2828	OpenWith.exe
2140	jusched.exe

Suspicious use of WriteProcessMemory 8 IoCs

description	pid	Process	procid_target
PID 2848 wrote to memory of 2796	2848	CritScript.exe	84
PID 2848 wrote to memory of 2796	2848	CritScript.exe	84
PID 2796 wrote to memory of 2688	2796	JUSCHED.EXE	86
PID 2796 wrote to memory of 2688	2796	JUSCHED.EXE	86
PID 2796 wrote to memory of 2140	2796	JUSCHED.EXE	88
PID 2796 wrote to memory of 2140	2796	JUSCHED.EXE	88
PID 2140 wrote to memory of 3908	2140	jusched.exe	89
PID 2140 wrote to memory of 3908	2140	jusched.exe	89

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\CritScript.exe
"C:\Users\Admin\AppData\Local\Temp\CritScript.exe"
1⤵
- Checks computer location settings
- System Location Discovery: System Language Discovery
- Modifies registry class
- Suspicious use of WriteProcessMemory
PID:2848
- C:\Users\Admin\AppData\Local\Temp\JUSCHED.EXE
  "C:\Users\Admin\AppData\Local\Temp\JUSCHED.EXE"
  2⤵
  - Executes dropped EXE
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of WriteProcessMemory
  PID:2796
- - C:\Windows\SYSTEM32\schtasks.exe
    "schtasks" /create /tn "Java Update Scheduler" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Java\jusched.exe" /rl HIGHEST /f
    3⤵
    - Scheduled Task/Job: Scheduled Task
    PID:2688
- - C:\Users\Admin\AppData\Roaming\Java\jusched.exe
    "C:\Users\Admin\AppData\Roaming\Java\jusched.exe"
    3⤵
    - Executes dropped EXE
    - Suspicious use of AdjustPrivilegeToken
    - Suspicious use of SetWindowsHookEx
    - Suspicious use of WriteProcessMemory
    PID:2140
  - - C:\Windows\SYSTEM32\schtasks.exe
      "schtasks" /create /tn "Java Update Scheduler" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Java\jusched.exe" /rl HIGHEST /f
      4⤵
      Scheduled Task/Job: Scheduled Task
      PID:3908

C:\Windows\system32\OpenWith.exe
C:\Windows\system32\OpenWith.exe -Embedding
1⤵
- Modifies registry class
- Suspicious use of SetWindowsHookEx
PID:2828

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Persistence

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Privilege Escalation

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Defense Evasion

Credential Access

Discovery

Query Registry

2

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\Microsoft\CLR_v4.0\UsageLogs\jusched.exe.log

Filesize
1KB

MD5
baf55b95da4a601229647f25dad12878

SHA1
abc16954ebfd213733c4493fc1910164d825cac8

SHA256
ee954c5d8156fd8890e582c716e5758ed9b33721258f10e758bdc31ccbcb1924

SHA512
24f502fedb1a305d0d7b08857ffc1db9b2359ff34e06d5748ecc84e35c985f29a20d9f0a533bea32d234ab37097ec0481620c63b14ac89b280e75e14d19fd545

Download Submit
C:\Users\Admin\AppData\Local\Temp\JUSCHED.EXE

Filesize
3.1MB

MD5
bd4dcbdfdb5fdc1f95bd1168f166153a

SHA1
9db60cf0f8a8b88d3c4601df25963536aaeb1884

SHA256
902bea9e4aeeed4e0b5d30a9cbcc6f9f1fc687b79c3fdde8258b94b410d1797a

SHA512
26ef32fe83a4e6c9c293910e96da431ba6b46b645969b9c56808d451875b0a3f4baad697362d7342f9d4822b84682b7705c2097839c796369503ffbfaa72aab2

Download Submit
memory/2140-24-0x00000000031F0000-0x0000000003240000-memory.dmp

Filesize
320KB

Download
memory/2140-25-0x000000001C340000-0x000000001C3F2000-memory.dmp

Filesize
712KB

Download
memory/2796-12-0x00007FFB34543000-0x00007FFB34545000-memory.dmp

Filesize
8KB

Download
memory/2796-14-0x00000000008C0000-0x0000000000BE4000-memory.dmp

Filesize
3.1MB

Download
memory/2796-15-0x00007FFB34540000-0x00007FFB35001000-memory.dmp

Filesize
10.8MB

Download
memory/2796-23-0x00007FFB34540000-0x00007FFB35001000-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