isrstealer | 520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b

General

Target

520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe
Size

448KB
MD5

526eae80ceb653f775d43213bfe6eb30
SHA1

b5d0e5514c8df40312ad708dac6677f64621de70
SHA256

520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b
SHA512

c2c22e35d83786b490c09055a4e28bd2b05952eabe84381e24368edfee21befee06924a844644bb8c92198bddb071c1f73a5007219067aafd35de80d20ad2163
SSDEEP

12288:+q/x7uJJAF++O+oWMa/2BNHhFvkKmKqB:+qtuJu0+nXO9fE

Score

10^/10

isrstealer collection 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 5 IoCs

resource	yara_rule
behavioral2/memory/4692-137-0x0000000000400000-0x0000000000442000-memory.dmp	family_isrstealer
behavioral2/memory/4692-139-0x0000000000400000-0x0000000000442000-memory.dmp	family_isrstealer
behavioral2/memory/4692-148-0x0000000000400000-0x0000000000442000-memory.dmp	family_isrstealer
behavioral2/memory/4692-151-0x0000000000400000-0x0000000000442000-memory.dmp	family_isrstealer
behavioral2/memory/4692-158-0x0000000000400000-0x0000000000442000-memory.dmp	family_isrstealer

NirSoft MailPassView 2 IoCs

Password recovery tool for various email clients

resource	yara_rule
behavioral2/memory/1944-156-0x0000000000400000-0x000000000041F000-memory.dmp	MailPassView
behavioral2/memory/1944-157-0x0000000000400000-0x000000000041F000-memory.dmp	MailPassView

Nirsoft 2 IoCs

resource	yara_rule
behavioral2/memory/1944-156-0x0000000000400000-0x000000000041F000-memory.dmp	Nirsoft
behavioral2/memory/1944-157-0x0000000000400000-0x000000000041F000-memory.dmp	Nirsoft

Executes dropped EXE 1 IoCs

pid	Process
4776	bot.exe

UPX packed file 8 IoCs

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

upx

resource	yara_rule
behavioral2/memory/4676-143-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral2/memory/4676-145-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral2/memory/4676-146-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral2/memory/4676-147-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral2/memory/1944-153-0x0000000000400000-0x000000000041F000-memory.dmp	upx
behavioral2/memory/1944-155-0x0000000000400000-0x000000000041F000-memory.dmp	upx
behavioral2/memory/1944-156-0x0000000000400000-0x000000000041F000-memory.dmp	upx
behavioral2/memory/1944-157-0x0000000000400000-0x000000000041F000-memory.dmp	upx

Checks computer location settings 2 TTPs 1 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-1-5-21-2629973501-4017243118-3254762364-1000\Control Panel\International\Geo\Nation	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe

Drops startup file 1 IoCs

description	ioc	Process
File created	C:\Users\Admin\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup\Pmkth8tnbTa.lnk	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe

Accesses Microsoft Outlook accounts 1 TTPs 1 IoCs

collection

Email Collection

T1114

description	ioc	Process
Key opened	\REGISTRY\USER\S-1-5-21-2629973501-4017243118-3254762364-1000\Software\Microsoft\Office\Outlook\OMI Account Manager\Accounts	svchost.exe

Suspicious use of SetThreadContext 3 IoCs

description	pid	Process	procid_target
PID 1612 set thread context of 4692	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe	81
PID 4692 set thread context of 4676	4692	svchost.exe	82
PID 4692 set thread context of 1944	4692	svchost.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 behavior: EnumeratesProcesses 6 IoCs

pid	Process
1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe
1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe
1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe
1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe
1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe
1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe

Suspicious use of AdjustPrivilegeToken 1 IoCs

description	pid	Process
Token: SeDebugPrivilege	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
4692	svchost.exe

Suspicious use of WriteProcessMemory 26 IoCs

description	pid	Process	procid_target
PID 1612 wrote to memory of 4776	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe	80
PID 1612 wrote to memory of 4776	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe	80
PID 1612 wrote to memory of 4776	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe	80
PID 1612 wrote to memory of 4692	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe	81
PID 1612 wrote to memory of 4692	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe	81
PID 1612 wrote to memory of 4692	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe	81
PID 1612 wrote to memory of 4692	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe	81
PID 1612 wrote to memory of 4692	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe	81
PID 1612 wrote to memory of 4692	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe	81
PID 1612 wrote to memory of 4692	1612	520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe	81
PID 4692 wrote to memory of 4676	4692	svchost.exe	82
PID 4692 wrote to memory of 4676	4692	svchost.exe	82
PID 4692 wrote to memory of 4676	4692	svchost.exe	82
PID 4692 wrote to memory of 4676	4692	svchost.exe	82
PID 4692 wrote to memory of 4676	4692	svchost.exe	82
PID 4692 wrote to memory of 4676	4692	svchost.exe	82
PID 4692 wrote to memory of 4676	4692	svchost.exe	82
PID 4692 wrote to memory of 4676	4692	svchost.exe	82
PID 4692 wrote to memory of 1944	4692	svchost.exe	85
PID 4692 wrote to memory of 1944	4692	svchost.exe	85
PID 4692 wrote to memory of 1944	4692	svchost.exe	85
PID 4692 wrote to memory of 1944	4692	svchost.exe	85
PID 4692 wrote to memory of 1944	4692	svchost.exe	85
PID 4692 wrote to memory of 1944	4692	svchost.exe	85
PID 4692 wrote to memory of 1944	4692	svchost.exe	85
PID 4692 wrote to memory of 1944	4692	svchost.exe	85

C:\Users\Admin\AppData\Local\Temp\520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe
"C:\Users\Admin\AppData\Local\Temp\520b8753ec07046c66e9df38fa53b95ffc442fca005b7b0daa30a289dc146b3b.exe"
1⤵
- Checks computer location settings
- Drops startup file
- Suspicious use of SetThreadContext
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:1612
- C:\Users\Admin\AppData\Local\Temp\bot.exe
  "C:\Users\Admin\AppData\Local\Temp\bot.exe"
  2⤵
  - Executes dropped EXE
  PID:4776
- C:\Windows\SysWOW64\svchost.exe
  "C:\Windows\system32\svchost.exe"
  2⤵
  - Suspicious use of SetThreadContext
  - Suspicious use of SetWindowsHookEx
  - Suspicious use of WriteProcessMemory
  PID:4692
- - C:\Windows\SysWOW64\svchost.exe
    /scomma "C:\Users\Admin\AppData\Local\Temp\h9S1a2TFJo.ini"
    3⤵
    PID:4676
- - C:\Windows\SysWOW64\svchost.exe
    /scomma "C:\Users\Admin\AppData\Local\Temp\KFrpcf1P0M.ini"
    3⤵
    - Accesses Microsoft Outlook accounts
    PID:1944

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Discovery

Query Registry

1

T1012

System Information Discovery

2

T1082

Lateral Movement

Collection

Email Collection

1

T1114

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

C:\Users\Admin\AppData\Local\Temp\bot.exe

Filesize
138KB

MD5
8bc34dd3c77324e7a0874caad19fde32

SHA1
da110f25eea78d95701391ad016417ae19b827bc

SHA256
cdf5867f5c5b7edf984965ec5444c58ed56456129a46b32a80891c10377c7805

SHA512
88ab3bf89206f721061dfd9842d2f86c5c2808cea2d00a992a4200c7ed1b4187d0979ad68a894ba5605f722d6f798106a9be5dff7548359f3ecb8fcbafd9d5bd

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

Filesize
138KB

MD5
8bc34dd3c77324e7a0874caad19fde32

SHA1
da110f25eea78d95701391ad016417ae19b827bc

SHA256
cdf5867f5c5b7edf984965ec5444c58ed56456129a46b32a80891c10377c7805

SHA512
88ab3bf89206f721061dfd9842d2f86c5c2808cea2d00a992a4200c7ed1b4187d0979ad68a894ba5605f722d6f798106a9be5dff7548359f3ecb8fcbafd9d5bd

Download Submit
C:\Users\Admin\AppData\Local\Temp\h9S1a2TFJo.ini

Filesize
5B

MD5
d1ea279fb5559c020a1b4137dc4de237

SHA1
db6f8988af46b56216a6f0daf95ab8c9bdb57400

SHA256
fcdcc2c46896915a1c695d6231f0fee336a668531b7a3da46178c80362546dba

SHA512
720e9c284f0559015312df7fe977563e5e16f48d3506e51eb4016adf7971924d352f740b030aa3adc81b6f65fd1dba12df06d10fa6c115074e5097e7ee0f08b3

Download Submit
memory/1612-132-0x0000000074A00000-0x0000000074FB1000-memory.dmp

Filesize
5.7MB

Download
memory/1612-149-0x0000000074A00000-0x0000000074FB1000-memory.dmp

Filesize
5.7MB

Download
memory/1944-155-0x0000000000400000-0x000000000041F000-memory.dmp

Filesize
124KB

Download
memory/1944-153-0x0000000000400000-0x000000000041F000-memory.dmp

Filesize
124KB

Download
memory/1944-156-0x0000000000400000-0x000000000041F000-memory.dmp

Filesize
124KB

Download
memory/1944-157-0x0000000000400000-0x000000000041F000-memory.dmp

Filesize
124KB

Download
memory/4676-143-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/4676-145-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/4676-146-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/4676-147-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/4692-137-0x0000000000400000-0x0000000000442000-memory.dmp

Filesize
264KB

Download
memory/4692-151-0x0000000000400000-0x0000000000442000-memory.dmp

Filesize
264KB

Download
memory/4692-148-0x0000000000400000-0x0000000000442000-memory.dmp

Filesize
264KB

Download
memory/4692-139-0x0000000000400000-0x0000000000442000-memory.dmp

Filesize
264KB

Download
memory/4692-158-0x0000000000400000-0x0000000000442000-memory.dmp

Filesize
264KB

Download

Analysis

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