Analysis
- max time kernel
122s - max time network
125s - platform
windows7_x64 - resource
win7-20231020-en - resource tags
arch:x64arch:x86image:win7-20231020-enlocale:en-usos:windows7-x64system - submitted
04/11/2023, 10:50
Behavioral task
behavioral1
Sample
Client-built.exe
Resource
win7-20231020-en
7 signatures
150 seconds
General
- Target Client-built.exe
- Size 3.1MB
- Sample231104-mxqa8sae22
- SHA256 62de60b59a7e50201894f528b124dc94c072c9db3904494d194b0c7f8be5a4f7
- MD5 5b6cf3311c43042e7c34d4245e837e49
- SHA1 2056489c9934a88ef0e0654c4ae2a26ee4b62f60
- SHA512 0b715f1c8d50333c35f8ef1d39fe7546b4e9bd9c5012e1df6dad739a0cefa2e56ea42837800e7b5b664e413a624156c559a5df1bbb9dacc6a3417ccc3556d966
- SSDEEP 49152:DvBt62XlaSFNWPjljiFa2RoUYIfkxNESEVk/ijLoGdHTHHB72eh2NT:Dvr62XlaSFNWPjljiFXRoUYI8x4v
- MD5 SHA1 SHA512 SSDEEP
Malware Config
Extracted
Family
-
quasar
Version
-
1.4.1
Botnet
-
Office04
C2
-
serverlolxd.ddns.net:4782
Mutex
-
d8c275e5-18fa-4e81-8ec8-a1df4d7051cd
Attributes
-
encryption_key
55134B4B269EA9FF5C0DE96378EBD7CC33C096F6
-
install_name
Client.exe
-
log_directory
Logs
-
reconnect_delay
3000
-
startup_key
Windows Update
-
subdirectory
SubDir
Signatures
- Quasar payload 1 IoCs
resource yara_rule behavioral1/memory/2660-0-0x0000000001220000-0x0000000001544000-memory.dmp family_quasar - Drops file in System32 directory 2 IoCs
description ioc Process File created C:\Windows\system32\SubDir\Client.exe Client-built.exe File opened for modification C:\Windows\system32\SubDir\Client.exe Client-built.exe - Creates scheduled task(s) 1 TTPs 1 IoCs
Schtasks is often used by malware for persistence or to perform post-infection execution.
pid Process 2368 schtasks.exe - Suspicious use of AdjustPrivilegeToken 1 IoCs
description pid Process Token: SeDebugPrivilege 2660 Client-built.exe - Suspicious use of WriteProcessMemory 3 IoCs
description pid Process procid_target PID 2660 wrote to memory of 2368 2660 Client-built.exe 28 PID 2660 wrote to memory of 2368 2660 Client-built.exe 28 PID 2660 wrote to memory of 2368 2660 Client-built.exe 28 - 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.
Processes
-
C:\Users\Admin\AppData\Local\Temp\Client-built.exe"C:\Users\Admin\AppData\Local\Temp\Client-built.exe"1⤵
- Drops file in System32 directory
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:2660 -
C:\Windows\system32\schtasks.exe"schtasks" /create /tn "Windows Update" /sc ONLOGON /tr "C:\Windows\system32\SubDir\Client.exe" /rl HIGHEST /f2⤵
- Creates scheduled task(s)
PID:2368
-