oski | 259a1e3d537f6e61c1683fe558a87e48da3ec44420cc0285da89c88bbf45375b

General

Target
RFQ-32986.exe
Size 287KB
Sample210723-2h4fc2xmnn
SHA256 259a1e3d537f6e61c1683fe558a87e48da3ec44420cc0285da89c88bbf45375b
MD5 528c56717b32a20c42b98eaf3f26cff5
SHA1 b6afa4b4b2540b89e48b1468a9e3e347ac567056
SHA512 86618685b3f245434bd0801ac78458a44748f4c5466f64f787ba554f3e7cb6ccc1718fae173312ca021a349e7e399d5a3f8650073394fe61a67c694e050a1f47
MD5 SHA1 SHA512

Score

10^/10

oski discovery infostealer spyware stealer

Malware Config

Extracted

Family

oski

C2

irkark.xyz

Signatures

Oski
Oski is an infostealer targeting browser data, crypto wallets.
infostealer oski
Downloads MZ/PE file

Loads dropped DLL 3 IoCs

pid	Process
1708	RFQ-32986.exe
1708	RFQ-32986.exe
1708	RFQ-32986.exe

Reads user/profile data of web browsers 2 TTPs
Infostealers often target stored browser data, which can include saved credentials etc.
spyware stealer

Data from Local System
T1005

Credentials in Files
T1081
Accesses cryptocurrency files/wallets, possible credential harvesting 2 TTPs
spyware

Data from Local System
T1005

Credentials in Files
T1081
Checks installed software on the system 1 TTPs
Looks up Uninstall key entries in the registry to enumerate software on the system.
discovery

Query Registry
T1012

Suspicious use of SetThreadContext 1 IoCs

description	pid	Process	procid_target
PID 1832 set thread context of 1708	1832	RFQ-32986.exe	75

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

System Information Discovery
T1082

Checks processor information in registry 2 TTPs 1 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	RFQ-32986.exe

Kills process with taskkill 1 IoCs

evasion

pid	Process
3992	taskkill.exe

Suspicious behavior: MapViewOfSection 1 IoCs

pid	Process
1832	RFQ-32986.exe

Suspicious use of AdjustPrivilegeToken 1 IoCs

description	pid	Process
Token: SeDebugPrivilege	3992	taskkill.exe

Suspicious use of WriteProcessMemory 10 IoCs

description	pid	Process	procid_target
PID 1832 wrote to memory of 1708	1832	RFQ-32986.exe	75
PID 1832 wrote to memory of 1708	1832	RFQ-32986.exe	75
PID 1832 wrote to memory of 1708	1832	RFQ-32986.exe	75
PID 1832 wrote to memory of 1708	1832	RFQ-32986.exe	75
PID 1708 wrote to memory of 1324	1708	RFQ-32986.exe	78
PID 1708 wrote to memory of 1324	1708	RFQ-32986.exe	78
PID 1708 wrote to memory of 1324	1708	RFQ-32986.exe	78
PID 1324 wrote to memory of 3992	1324	cmd.exe	80
PID 1324 wrote to memory of 3992	1324	cmd.exe	80
PID 1324 wrote to memory of 3992	1324	cmd.exe	80

C:\Users\Admin\AppData\Local\Temp\RFQ-32986.exe
"C:\Users\Admin\AppData\Local\Temp\RFQ-32986.exe"
1⤵
- Suspicious use of SetThreadContext
- Suspicious behavior: MapViewOfSection
- Suspicious use of WriteProcessMemory
PID:1832
- C:\Users\Admin\AppData\Local\Temp\RFQ-32986.exe
  "C:\Users\Admin\AppData\Local\Temp\RFQ-32986.exe"
  2⤵
  - Loads dropped DLL
  - Checks processor information in registry
  - Suspicious use of WriteProcessMemory
  PID:1708
- - C:\Windows\SysWOW64\cmd.exe
    "C:\Windows\System32\cmd.exe" /c taskkill /pid 1708 & erase C:\Users\Admin\AppData\Local\Temp\RFQ-32986.exe & RD /S /Q C:\\ProgramData\\009753218485440\\* & exit
    3⤵
    - Suspicious use of WriteProcessMemory
    PID:1324
  - - C:\Windows\SysWOW64\taskkill.exe
      taskkill /pid 1708
      4⤵
      Kills process with taskkill
      Suspicious use of AdjustPrivilegeToken
      PID:3992

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Credentials in Files

2

T1081

Discovery

Query Registry

2

T1012

System Information Discovery

2

T1082

Lateral Movement

Collection

Data from Local System

2

T1005

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

memory/1708-116-0x0000000000400000-0x0000000000438000-memory.dmp

Download

memory/1832-115-0x00000000001E0000-0x00000000001E2000-memory.dmp