isrstealer | 92aab46d0e0b52f33f241a548d95758ecd23a78024626a6b5c190000d172dda0

General

Target

92aab46d0e0b52f33f241a548d95758ecd23a78024626a6b5c190000d172dda0.exe
Size

673KB
MD5

20ef16a722778d92f6bf93d3310eb9ea
SHA1

3b6c0364751e892749c77e40b2ec75c8a71e3f48
SHA256

92aab46d0e0b52f33f241a548d95758ecd23a78024626a6b5c190000d172dda0
SHA512

9d596b365c4fbfbbeb75fb643322ef392bab666a106aa349692a15c5d85a94e67a0d6ed09035ac2b3cf779aa82e653efbebc8311f766816297e349d58e059a7e
SSDEEP

6144:8dhylx6z9cdIKCC0ef//uXltKc+LVsz9b86dhyeK62/rZAlPbLxYMbUyPnQ/txC+:s62cdFeCXuLKcCVsz6OtU/WPpYDxAO

Score

10^/10

isrstealer persistence 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
behavioral2/memory/3284-138-0x0000000000400000-0x0000000000435000-memory.dmp	family_isrstealer
behavioral2/memory/3284-148-0x0000000000400000-0x0000000000435000-memory.dmp	family_isrstealer
behavioral2/memory/3284-156-0x0000000000400000-0x0000000000435000-memory.dmp	family_isrstealer

Modifies WinLogon for persistence 2 TTPs 1 IoCs

persistence

Winlogon Helper DLL

T1004

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\USER\S-1-5-21-929662420-1054238289-2961194603-1000\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\shell = "explorer.exe,C:\\Users\\Admin\\AppData\\Local\\Temp\\winini.exe"	reg.exe

Executes dropped EXE 3 IoCs

pid	Process
5076	winini.exe
3284	cvtres.exe
4188	cvtres.exe

UPX packed file 4 IoCs

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

upx

resource	yara_rule
behavioral2/memory/4188-147-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral2/memory/4188-151-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral2/memory/4188-153-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral2/memory/4188-154-0x0000000000400000-0x0000000000453000-memory.dmp	upx

Checks computer location settings 2 TTPs 2 IoCs

Looks up country code configured in the registry, likely geofence.

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key value queried	\REGISTRY\USER\S-1-5-21-929662420-1054238289-2961194603-1000\Control Panel\International\Geo\Nation	92aab46d0e0b52f33f241a548d95758ecd23a78024626a6b5c190000d172dda0.exe
Key value queried	\REGISTRY\USER\S-1-5-21-929662420-1054238289-2961194603-1000\Control Panel\International\Geo\Nation	winini.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

Suspicious use of SetThreadContext 2 IoCs

description	pid	Process	procid_target
PID 5076 set thread context of 3284	5076	winini.exe	82
PID 3284 set thread context of 4188	3284	cvtres.exe	85

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

System Information Discovery
T1082

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
3284	cvtres.exe

Suspicious use of WriteProcessMemory 25 IoCs

description	pid	Process	procid_target
PID 2820 wrote to memory of 5076	2820	92aab46d0e0b52f33f241a548d95758ecd23a78024626a6b5c190000d172dda0.exe	81
PID 2820 wrote to memory of 5076	2820	92aab46d0e0b52f33f241a548d95758ecd23a78024626a6b5c190000d172dda0.exe	81
PID 2820 wrote to memory of 5076	2820	92aab46d0e0b52f33f241a548d95758ecd23a78024626a6b5c190000d172dda0.exe	81
PID 5076 wrote to memory of 3284	5076	winini.exe	82
PID 5076 wrote to memory of 3284	5076	winini.exe	82
PID 5076 wrote to memory of 3284	5076	winini.exe	82
PID 5076 wrote to memory of 3284	5076	winini.exe	82
PID 5076 wrote to memory of 3284	5076	winini.exe	82
PID 5076 wrote to memory of 3284	5076	winini.exe	82
PID 5076 wrote to memory of 3284	5076	winini.exe	82
PID 5076 wrote to memory of 3284	5076	winini.exe	82
PID 5076 wrote to memory of 4232	5076	winini.exe	83
PID 5076 wrote to memory of 4232	5076	winini.exe	83
PID 5076 wrote to memory of 4232	5076	winini.exe	83
PID 3284 wrote to memory of 4188	3284	cvtres.exe	85
PID 3284 wrote to memory of 4188	3284	cvtres.exe	85
PID 3284 wrote to memory of 4188	3284	cvtres.exe	85
PID 3284 wrote to memory of 4188	3284	cvtres.exe	85
PID 3284 wrote to memory of 4188	3284	cvtres.exe	85
PID 3284 wrote to memory of 4188	3284	cvtres.exe	85
PID 3284 wrote to memory of 4188	3284	cvtres.exe	85
PID 3284 wrote to memory of 4188	3284	cvtres.exe	85
PID 4232 wrote to memory of 1740	4232	cmd.exe	86
PID 4232 wrote to memory of 1740	4232	cmd.exe	86
PID 4232 wrote to memory of 1740	4232	cmd.exe	86

C:\Users\Admin\AppData\Local\Temp\92aab46d0e0b52f33f241a548d95758ecd23a78024626a6b5c190000d172dda0.exe
"C:\Users\Admin\AppData\Local\Temp\92aab46d0e0b52f33f241a548d95758ecd23a78024626a6b5c190000d172dda0.exe"
1⤵
- Checks computer location settings
- Suspicious use of WriteProcessMemory
PID:2820
- C:\Users\Admin\AppData\Local\Temp\winini.exe
  "C:\Users\Admin\AppData\Local\Temp\winini.exe" cvtres.exe
  2⤵
  - Executes dropped EXE
  - Checks computer location settings
  - Suspicious use of SetThreadContext
  - Suspicious use of WriteProcessMemory
  PID:5076
- - C:\Users\Admin\AppData\Local\Temp\cvtres.exe
    C:\Users\Admin\AppData\Local\Temp\cvtres.exe
    3⤵
    - Executes dropped EXE
    - Suspicious use of SetThreadContext
    - Suspicious use of SetWindowsHookEx
    - Suspicious use of WriteProcessMemory
    PID:3284
  - - C:\Users\Admin\AppData\Local\Temp\cvtres.exe
      /scomma "C:\Users\Admin\AppData\Local\Temp\DENkyEoTx0.ini"
      4⤵
      Executes dropped EXE
      PID:4188
- - C:\Windows\SysWOW64\cmd.exe
    "C:\Windows\System32\cmd.exe" /c reg add "HKCU\Software\Microsoft\Windows NT\CurrentVersion\Winlogon" /f /v shell /t REG_SZ /d explorer.exe,"C:\Users\Admin\AppData\Local\Temp\winini.exe"
    3⤵
    - Suspicious use of WriteProcessMemory
    PID:4232
  - - C:\Windows\SysWOW64\reg.exe
      reg add "HKCU\Software\Microsoft\Windows NT\CurrentVersion\Winlogon" /f /v shell /t REG_SZ /d explorer.exe,"C:\Users\Admin\AppData\Local\Temp\winini.exe"
      4⤵
      Modifies WinLogon for persistence
      PID:1740

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Winlogon Helper DLL

1

T1004

Privilege Escalation

Defense Evasion

Modify Registry

1

T1112

Credential Access

Credentials in Files

1

T1081

Discovery

Query Registry

1

T1012

System Information Discovery

2

T1082

Lateral Movement

Collection

Data from Local System

1

T1005

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

C:\Users\Admin\AppData\Local\Temp\DENkyEoTx0.ini

Filesize
5B

MD5
d1ea279fb5559c020a1b4137dc4de237

SHA1
db6f8988af46b56216a6f0daf95ab8c9bdb57400

SHA256
fcdcc2c46896915a1c695d6231f0fee336a668531b7a3da46178c80362546dba

SHA512
720e9c284f0559015312df7fe977563e5e16f48d3506e51eb4016adf7971924d352f740b030aa3adc81b6f65fd1dba12df06d10fa6c115074e5097e7ee0f08b3

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

Filesize
1024B

MD5
54b1c45da8980b32759042e2c3c78dfb

SHA1
11e8bc2db98786c69e5dadf53d00ff3ee03d64f8

SHA256
9d5efce48ed68dcb4caaa7fbecaf47ce2cab0a023afc6ceed682d1d532823773

SHA512
73169989b97a032fe923272fbe4bc27be77e491d125b360120fc1e02419d99f807b1f62a3edaff85ebfd16e9c240ec295be9431cfe4d6c353f0cf0dbeec4d2ac

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

Filesize
1024B

MD5
54b1c45da8980b32759042e2c3c78dfb

SHA1
11e8bc2db98786c69e5dadf53d00ff3ee03d64f8

SHA256
9d5efce48ed68dcb4caaa7fbecaf47ce2cab0a023afc6ceed682d1d532823773

SHA512
73169989b97a032fe923272fbe4bc27be77e491d125b360120fc1e02419d99f807b1f62a3edaff85ebfd16e9c240ec295be9431cfe4d6c353f0cf0dbeec4d2ac

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

Filesize
1024B

MD5
54b1c45da8980b32759042e2c3c78dfb

SHA1
11e8bc2db98786c69e5dadf53d00ff3ee03d64f8

SHA256
9d5efce48ed68dcb4caaa7fbecaf47ce2cab0a023afc6ceed682d1d532823773

SHA512
73169989b97a032fe923272fbe4bc27be77e491d125b360120fc1e02419d99f807b1f62a3edaff85ebfd16e9c240ec295be9431cfe4d6c353f0cf0dbeec4d2ac

Download Submit
C:\Users\Admin\AppData\Local\Temp\winini.exe

Filesize
573KB

MD5
4e6acfd4ceb58565dd19c83c959c5e6b

SHA1
e9d448c22bf2ef2d71b7a3550dd77bd42ce24f9c

SHA256
438e2c3bd77ca8fd5207b7ad59442518a4d45eced33e604277f43fecd3af8c79

SHA512
eda6bd8e10bd005ab4c7a2bfc01b7875e633b424c212bf171d54dda5f4f45cbbee15cb42ab6591ddc10f241f36af1570ad48fba4aa361bfe6f398ea760d8f71c

Download Submit
C:\Users\Admin\AppData\Local\Temp\winini.exe

Filesize
573KB

MD5
4e6acfd4ceb58565dd19c83c959c5e6b

SHA1
e9d448c22bf2ef2d71b7a3550dd77bd42ce24f9c

SHA256
438e2c3bd77ca8fd5207b7ad59442518a4d45eced33e604277f43fecd3af8c79

SHA512
eda6bd8e10bd005ab4c7a2bfc01b7875e633b424c212bf171d54dda5f4f45cbbee15cb42ab6591ddc10f241f36af1570ad48fba4aa361bfe6f398ea760d8f71c

Download Submit
memory/2820-137-0x00000000753F0000-0x00000000759A1000-memory.dmp

Filesize
5.7MB

Download
memory/2820-132-0x00000000753F0000-0x00000000759A1000-memory.dmp

Filesize
5.7MB

Download
memory/3284-156-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/3284-138-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/3284-148-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/4188-151-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/4188-147-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/4188-153-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/4188-154-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/5076-145-0x00000000753F0000-0x00000000759A1000-memory.dmp

Filesize
5.7MB

Download

Analysis

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