isrstealer | 038c8da9639da5bbf5049937b49bc4783f8afeb907903a6c7b12cbed4e697659

General

Target

JaffaCakes118_2589da5a4c697b83b4bef9dccdd65c10.exe
Size

827KB
MD5

2589da5a4c697b83b4bef9dccdd65c10
SHA1

356a0f37f0b9271aceb33c1177bb1e27edcf74d5
SHA256

038c8da9639da5bbf5049937b49bc4783f8afeb907903a6c7b12cbed4e697659
SHA512

e3b67d20836750b27ba6408ec4c7a405a8c00882aa9819ca33a0fd11d0e529d209c90f213485bae28bb02810c92d546006d72b21f3bbf1f988bbfd2b11759dbc
SSDEEP

12288:slMB8Ai4XCNGijE4DFogliG4jTEzP25oc5ccxnmf7T:wMB8Z77td4ncT25L5Pmf7T

Score

10^/10

isrstealer discovery spyware stealer trojan upx

Malware Config

Signatures

ISR Stealer
ISR Stealer is a modified version of Hackhound Stealer written in visual basic.
trojan stealer isrstealer

ISR Stealer payload 3 IoCs

resource	yara_rule
behavioral1/memory/2444-28-0x0000000000400000-0x0000000000435000-memory.dmp	family_isrstealer
behavioral1/memory/2444-24-0x0000000000400000-0x0000000000435000-memory.dmp	family_isrstealer
behavioral1/memory/2444-49-0x0000000000400000-0x0000000000435000-memory.dmp	family_isrstealer

Isrstealer family
isrstealer

Executes dropped EXE 3 IoCs

pid	Process
2860	KvtwL.exe
2444	cvtres.exe
1940	cvtres.exe

Loads dropped DLL 4 IoCs

pid	Process
2232	JaffaCakes118_2589da5a4c697b83b4bef9dccdd65c10.exe
2232	JaffaCakes118_2589da5a4c697b83b4bef9dccdd65c10.exe
2860	KvtwL.exe
2444	cvtres.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

Suspicious use of SetThreadContext 2 IoCs

description	pid	Process	procid_target
PID 2860 set thread context of 2444	2860	KvtwL.exe	31
PID 2444 set thread context of 1940	2444	cvtres.exe	32

UPX packed file 5 IoCs

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

upx

resource	yara_rule
behavioral1/memory/1940-36-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral1/memory/1940-42-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral1/memory/1940-41-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral1/memory/1940-40-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral1/memory/1940-44-0x0000000000400000-0x0000000000453000-memory.dmp	upx

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 4 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	JaffaCakes118_2589da5a4c697b83b4bef9dccdd65c10.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	KvtwL.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cvtres.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cvtres.exe

Suspicious behavior: EnumeratesProcesses 2 IoCs

pid	Process
2860	KvtwL.exe
2860	KvtwL.exe

Suspicious use of AdjustPrivilegeToken 1 IoCs

description	pid	Process
Token: SeDebugPrivilege	2860	KvtwL.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
2444	cvtres.exe

Suspicious use of WriteProcessMemory 21 IoCs

description	pid	Process	procid_target
PID 2232 wrote to memory of 2860	2232	JaffaCakes118_2589da5a4c697b83b4bef9dccdd65c10.exe	30
PID 2232 wrote to memory of 2860	2232	JaffaCakes118_2589da5a4c697b83b4bef9dccdd65c10.exe	30
PID 2232 wrote to memory of 2860	2232	JaffaCakes118_2589da5a4c697b83b4bef9dccdd65c10.exe	30
PID 2232 wrote to memory of 2860	2232	JaffaCakes118_2589da5a4c697b83b4bef9dccdd65c10.exe	30
PID 2860 wrote to memory of 2444	2860	KvtwL.exe	31
PID 2860 wrote to memory of 2444	2860	KvtwL.exe	31
PID 2860 wrote to memory of 2444	2860	KvtwL.exe	31
PID 2860 wrote to memory of 2444	2860	KvtwL.exe	31
PID 2860 wrote to memory of 2444	2860	KvtwL.exe	31
PID 2860 wrote to memory of 2444	2860	KvtwL.exe	31
PID 2860 wrote to memory of 2444	2860	KvtwL.exe	31
PID 2860 wrote to memory of 2444	2860	KvtwL.exe	31
PID 2444 wrote to memory of 1940	2444	cvtres.exe	32
PID 2444 wrote to memory of 1940	2444	cvtres.exe	32
PID 2444 wrote to memory of 1940	2444	cvtres.exe	32
PID 2444 wrote to memory of 1940	2444	cvtres.exe	32
PID 2444 wrote to memory of 1940	2444	cvtres.exe	32
PID 2444 wrote to memory of 1940	2444	cvtres.exe	32
PID 2444 wrote to memory of 1940	2444	cvtres.exe	32
PID 2444 wrote to memory of 1940	2444	cvtres.exe	32
PID 2444 wrote to memory of 1940	2444	cvtres.exe	32

C:\Users\Admin\AppData\Local\Temp\JaffaCakes118_2589da5a4c697b83b4bef9dccdd65c10.exe
"C:\Users\Admin\AppData\Local\Temp\JaffaCakes118_2589da5a4c697b83b4bef9dccdd65c10.exe"
1⤵
- Loads dropped DLL
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:2232
- C:\Users\Admin\AppData\Local\Temp\KvtwL.exe
  "C:\Users\Admin\AppData\Local\Temp\KvtwL.exe"
  2⤵
  - Executes dropped EXE
  - Loads dropped DLL
  - Suspicious use of SetThreadContext
  - System Location Discovery: System Language Discovery
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of WriteProcessMemory
  PID:2860
- - C:\Users\Admin\AppData\Local\Temp\cvtres.exe
    C:\Users\Admin\AppData\Local\Temp\\cvtres.exe
    3⤵
    - Executes dropped EXE
    - Loads dropped DLL
    - Suspicious use of SetThreadContext
    - System Location Discovery: System Language Discovery
    - Suspicious use of SetWindowsHookEx
    - Suspicious use of WriteProcessMemory
    PID:2444
  - - C:\Users\Admin\AppData\Local\Temp\cvtres.exe
      /scomma "C:\Users\Admin\AppData\Local\Temp\PEYggS12XM.ini"
      4⤵
      Executes dropped EXE
      System Location Discovery: System Language Discovery
      PID:1940

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Credentials from Password Stores

1

T1555

Credentials from Web Browsers

1

T1555.003

Unsecured Credentials

1

T1552

Credentials In Files

1

T1552.001

Discovery

System Information Discovery

1

T1082

System Location Discovery

1

T1614

System Language Discovery

1

T1614.001

Lateral Movement

Collection

Data from Local System

1

T1005

Command and Control

Exfiltration

Impact

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Downloads

C:\Users\Admin\AppData\Local\Temp\PEYggS12XM.ini

Filesize
5B

MD5
d1ea279fb5559c020a1b4137dc4de237

SHA1
db6f8988af46b56216a6f0daf95ab8c9bdb57400

SHA256
fcdcc2c46896915a1c695d6231f0fee336a668531b7a3da46178c80362546dba

SHA512
720e9c284f0559015312df7fe977563e5e16f48d3506e51eb4016adf7971924d352f740b030aa3adc81b6f65fd1dba12df06d10fa6c115074e5097e7ee0f08b3

Download Submit
\Users\Admin\AppData\Local\Temp\KvtwL.exe

Filesize
295KB

MD5
3b9cb4e2682bff76dad8a06a54fe3c68

SHA1
6e5fd981dc8e09e53f7741b04438160328481571

SHA256
b66f7c8317482209ae76910e80188763fb5c218670148c9d38ba0f0e5e3edf66

SHA512
43fed22c6cc7a4d496adaa7285f8eae97f87c70c8368269b09d66c110874566f2b42101c25123677919427cb7cd2061ef0776c53e1af503865d9094a692d927b

Download Submit
\Users\Admin\AppData\Local\Temp\cvtres.exe

Filesize
31KB

MD5
ed797d8dc2c92401985d162e42ffa450

SHA1
0f02fc517c7facc4baefde4fe9467fb6488ebabe

SHA256
b746362010a101cb5931bc066f0f4d3fc740c02a68c1f37fc3c8e6c87fd7cb1e

SHA512
e831a6ff987f3ef29982da16afad06938b68eddd43c234ba88d1c96a1b5547f2284baf35cbb3a5bfd75e7f0445d14daa014e0ba00b4db72c67f83f0a314c80c2

Download Submit
memory/1940-36-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/1940-44-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/1940-40-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/1940-41-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/1940-42-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/2232-1-0x0000000074B30000-0x00000000750DB000-memory.dmp

Filesize
5.7MB

Download
memory/2232-2-0x0000000074B30000-0x00000000750DB000-memory.dmp

Filesize
5.7MB

Download
memory/2232-13-0x0000000074B30000-0x00000000750DB000-memory.dmp

Filesize
5.7MB

Download
memory/2232-0-0x0000000074B31000-0x0000000074B32000-memory.dmp

Filesize
4KB

Download
memory/2444-26-0x000000007EFDE000-0x000000007EFDF000-memory.dmp

Filesize
4KB

Download
memory/2444-20-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/2444-24-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/2444-28-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/2444-22-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/2444-49-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/2860-14-0x0000000074B30000-0x00000000750DB000-memory.dmp

Filesize
5.7MB

Download
memory/2860-15-0x0000000074B30000-0x00000000750DB000-memory.dmp

Filesize
5.7MB

Download
memory/2860-47-0x0000000074B30000-0x00000000750DB000-memory.dmp

Filesize
5.7MB

Download
memory/2860-48-0x0000000074B30000-0x00000000750DB000-memory.dmp

Filesize
5.7MB

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Analysis

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