b92e1ee2bfeb614cbc96df222bd9dd085ce48185e350b5fd6d85d681897ff454

Analysis

max time kernel
122s
max time network
124s
platform
windows7_x64
resource
win7-20240708-en
resource tags

arch:x64arch:x86image:win7-20240708-enlocale:en-usos:windows7-x64system
submitted
30-09-2024 09:24

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General

Target

efsdll.dll
Size

188KB
MD5

a380576572ca1a7b23ea2c05fbdadfa4
SHA1

3755d18417b1338d5fe1b3560480a3fed558be08
SHA256

9a55de57f24a2ed96759a8e8cef0470ff09e79174dfc7220d36a586c4ecdb01f
SHA512

58352bbee22a2a3a37547f398924b447601a9d9dae532d04255f5524c4bad913ea48a142880f2cbf2b36fb28d2820d1fe967c5a9e5ccfc56c9b04dbc7da5ba48
SSDEEP

3072:naUfLpn9ocdukzaOjBh8nSf35/IexSzGbflbD+fDyBGdx6Mxo8tsSVNXRyz1s4ml:nXDp9ocdHjySP5V7l/+8GdxNq8tfVNBn

Score

6^/10

discovery upx

Malware Config

Signatures

Enumerates connected drives 3 TTPs 2 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)	\??\D:	rundll32.exe
File opened (read-only)	\??\F:	rundll32.exe

Drops file in System32 directory 1 IoCs

description	ioc	Process
File opened for modification	C:\Windows\SysWOW64\efsdll.log	rundll32.exe

UPX packed file 2 IoCs

Detects executables packed with UPX/modified UPX open source packer.

upx

resource	yara_rule
behavioral23/memory/2552-0-0x0000000010000000-0x00000000102D9000-memory.dmp	upx
behavioral23/memory/2552-2-0x0000000010000000-0x00000000102D9000-memory.dmp	upx

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

Suspicious use of WriteProcessMemory 7 IoCs

description	pid	Process	procid_target
PID 1700 wrote to memory of 2552	1700	rundll32.exe	30
PID 1700 wrote to memory of 2552	1700	rundll32.exe	30
PID 1700 wrote to memory of 2552	1700	rundll32.exe	30
PID 1700 wrote to memory of 2552	1700	rundll32.exe	30
PID 1700 wrote to memory of 2552	1700	rundll32.exe	30
PID 1700 wrote to memory of 2552	1700	rundll32.exe	30
PID 1700 wrote to memory of 2552	1700	rundll32.exe	30

C:\Windows\system32\rundll32.exe
rundll32.exe C:\Users\Admin\AppData\Local\Temp\efsdll.dll,#1
1⤵
- Suspicious use of WriteProcessMemory
PID:1700
- C:\Windows\SysWOW64\rundll32.exe
  rundll32.exe C:\Users\Admin\AppData\Local\Temp\efsdll.dll,#1
  2⤵
  - Enumerates connected drives
  - Drops file in System32 directory
  - System Location Discovery: System Language Discovery
  PID:2552

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Discovery

Peripheral Device Discovery

T1120

Query Registry

T1012

System Information Discovery

T1082

System Location Discovery

T1614

System Language Discovery

T1614.001

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

memory/2552-0-0x0000000010000000-0x00000000102D9000-memory.dmp

Filesize
2.8MB

Download
memory/2552-2-0x0000000010000000-0x00000000102D9000-memory.dmp

Filesize
2.8MB

Download