b861b9dfb02d48e66efcc2fe31315f6fcf5e8a13c66efe5d32c892ba634a24fe

General

Target
b861b9dfb02d48e66efcc2fe31315f6fcf5e8a13c66efe5d32c892ba634a24fe.dll
Size 188KB
Sample241109-ddwt8sylgr
SHA256 b861b9dfb02d48e66efcc2fe31315f6fcf5e8a13c66efe5d32c892ba634a24fe
MD5 31ad72b19e3a6b9d23e207c938e0641a
SHA1 f001891f22f54a48b025a54d3eeebd92d5efd0ed
SHA512 99e11ece650aa45fdc41292752048a69f002f8cbb5b119d4cc6c4f2f2bea6152ce29ce297d432ae52861684008710ce980875cb43917ae8e9a61b85c66bb6ddc
SSDEEP 3072:Cri0+utSCXQJdqByftkViecNemfh0N5Wlu/gX6ASMqsCAn+/B87CVKrNyGTb+:CyrJdqByftkVbgQen+p7obTb+
MD5 SHA1 SHA512 SSDEEP

Score

8^/10

bootkit discovery persistence spyware stealer

Malware Config

Signatures

Blocklisted process makes network request 10 IoCs

flow	pid	Process
11	4764	rundll32.exe
17	4764	rundll32.exe
23	4764	rundll32.exe
24	4764	rundll32.exe
25	4764	rundll32.exe
38	4764	rundll32.exe
39	4764	rundll32.exe
42	4764	rundll32.exe
48	4764	rundll32.exe
49	4764	rundll32.exe

Reads user/profile data of web browsers 3 TTPs
Infostealers often target stored browser data, which can include saved credentials etc.
spyware stealer

Data from Local System
T1005

Credentials In Files
T1552.001

Credentials from Web Browsers
T1555.003

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-1-5-21-1045960512-3948844814-3059691613-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\Cache = "C:\\Windows\\SysWOW64\\rundll32.exe \"C:\\Users\\Admin\\AppData\\Local\\Temp\\b861b9dfb02d48e66efcc2fe31315f6fcf5e8a13c66efe5d32c892ba634a24fe.dll\",Cache"	rundll32.exe

Enumerates connected drives 3 TTPs 23 IoCs

Attempts to read the root path of hard drives other than the default C: drive.

Query Registry

T1012

Peripheral Device Discovery

T1120

System Information Discovery

T1082

description	ioc	Process
File opened (read-only)	\??\s:	rundll32.exe
File opened (read-only)	\??\a:	rundll32.exe
File opened (read-only)	\??\b:	rundll32.exe
File opened (read-only)	\??\g:	rundll32.exe
File opened (read-only)	\??\j:	rundll32.exe
File opened (read-only)	\??\p:	rundll32.exe
File opened (read-only)	\??\r:	rundll32.exe
File opened (read-only)	\??\k:	rundll32.exe
File opened (read-only)	\??\l:	rundll32.exe
File opened (read-only)	\??\q:	rundll32.exe
File opened (read-only)	\??\t:	rundll32.exe
File opened (read-only)	\??\v:	rundll32.exe
File opened (read-only)	\??\w:	rundll32.exe
File opened (read-only)	\??\i:	rundll32.exe
File opened (read-only)	\??\m:	rundll32.exe
File opened (read-only)	\??\n:	rundll32.exe
File opened (read-only)	\??\o:	rundll32.exe
File opened (read-only)	\??\u:	rundll32.exe
File opened (read-only)	\??\e:	rundll32.exe
File opened (read-only)	\??\h:	rundll32.exe
File opened (read-only)	\??\x:	rundll32.exe
File opened (read-only)	\??\y:	rundll32.exe
File opened (read-only)	\??\z:	rundll32.exe

Writes to the Master Boot Record (MBR) 1 TTPs 1 IoCs

Bootkits write to the MBR to gain persistence at a level below the operating system.

bootkit persistence

Bootkit

T1542.003

description	ioc	Process
File opened for modification	\??\PHYSICALDRIVE0	rundll32.exe

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	rundll32.exe

Checks processor information in registry 2 TTPs 2 IoCs

Processor information is often read in order to detect sandboxing environments.

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\ProcessorNameString	rundll32.exe
Key opened	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0	rundll32.exe

Suspicious behavior: EnumeratesProcesses 4 IoCs

pid	Process
4764	rundll32.exe
4764	rundll32.exe
4764	rundll32.exe
4764	rundll32.exe

Suspicious use of AdjustPrivilegeToken 1 IoCs

description	pid	Process
Token: SeDebugPrivilege	4764	rundll32.exe

Suspicious use of WriteProcessMemory 3 IoCs

description	pid	Process	procid_target
PID 1900 wrote to memory of 4764	1900	rundll32.exe	83
PID 1900 wrote to memory of 4764	1900	rundll32.exe	83
PID 1900 wrote to memory of 4764	1900	rundll32.exe	83

C:\Windows\system32\rundll32.exe
rundll32.exe C:\Users\Admin\AppData\Local\Temp\b861b9dfb02d48e66efcc2fe31315f6fcf5e8a13c66efe5d32c892ba634a24fe.dll,#1
1⤵
- Suspicious use of WriteProcessMemory
PID:1900
- C:\Windows\SysWOW64\rundll32.exe
  rundll32.exe C:\Users\Admin\AppData\Local\Temp\b861b9dfb02d48e66efcc2fe31315f6fcf5e8a13c66efe5d32c892ba634a24fe.dll,#1
  2⤵
  - Blocklisted process makes network request
  - Adds Run key to start application
  - Enumerates connected drives
  - Writes to the Master Boot Record (MBR)
  - System Location Discovery: System Language Discovery
  - Checks processor information in registry
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:4764