isrstealer | b3de5859d79cba761fb3f22ffb4f2c674452d4ddedc2732b9a1bc0fbed0926b9

General

Target

b3de5859d79cba761fb3f22ffb4f2c674452d4ddedc2732b9a1bc0fbed0926b9.exe
Size

360KB
MD5

5d0c3fed471d11d19e9dc10103bead3e
SHA1

865d8950c66519d206261926538e40073a252954
SHA256

b3de5859d79cba761fb3f22ffb4f2c674452d4ddedc2732b9a1bc0fbed0926b9
SHA512

76285d896b45586660456b646910a822203325d57789abfb4619974620f18c370cdd9988331f8fe1283d0c16431d1c46aeae7e9fe2e55537d1ef7a041bac8f50
SSDEEP

6144:8xM8Skop7Dv+mmaX75j/12D3URRUAwDirJWjnc9gxuDFBHGFgiw:4cpHv+baX7n2QzUBDRjnc9ScFZG0

Score

10^/10

isrstealer collection persistence 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 6 IoCs

resource	yara_rule
behavioral2/memory/100-137-0x0000000000400000-0x0000000000442000-memory.dmp	family_isrstealer
behavioral2/memory/100-139-0x0000000000400000-0x0000000000442000-memory.dmp	family_isrstealer
behavioral2/memory/100-141-0x0000000000401180-mapping.dmp	family_isrstealer
behavioral2/memory/100-145-0x0000000000400000-0x0000000000442000-memory.dmp	family_isrstealer
behavioral2/memory/100-151-0x0000000000400000-0x0000000000442000-memory.dmp	family_isrstealer
behavioral2/memory/100-160-0x0000000000400000-0x0000000000442000-memory.dmp	family_isrstealer

NirSoft MailPassView 3 IoCs

Password recovery tool for various email clients

resource	yara_rule
behavioral2/memory/864-157-0x0000000000400000-0x000000000041F000-memory.dmp	MailPassView
behavioral2/memory/864-158-0x0000000000400000-0x000000000041F000-memory.dmp	MailPassView
behavioral2/memory/864-159-0x0000000000400000-0x000000000041F000-memory.dmp	MailPassView

Nirsoft 3 IoCs

resource	yara_rule
behavioral2/memory/864-157-0x0000000000400000-0x000000000041F000-memory.dmp	Nirsoft
behavioral2/memory/864-158-0x0000000000400000-0x000000000041F000-memory.dmp	Nirsoft
behavioral2/memory/864-159-0x0000000000400000-0x000000000041F000-memory.dmp	Nirsoft

Executes dropped EXE 4 IoCs

pid	Process
2572	winlogon.exe
100	winlogon.exe
4260	winlogon.exe
864	winlogon.exe

UPX packed file 5 IoCs

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

upx

resource	yara_rule
behavioral2/memory/864-153-0x0000000000400000-0x000000000041F000-memory.dmp	upx
behavioral2/memory/864-156-0x0000000000400000-0x000000000041F000-memory.dmp	upx
behavioral2/memory/864-157-0x0000000000400000-0x000000000041F000-memory.dmp	upx
behavioral2/memory/864-158-0x0000000000400000-0x000000000041F000-memory.dmp	upx
behavioral2/memory/864-159-0x0000000000400000-0x000000000041F000-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-1-5-21-4246620582-653642754-1174164128-1000\Control Panel\International\Geo\Nation	b3de5859d79cba761fb3f22ffb4f2c674452d4ddedc2732b9a1bc0fbed0926b9.exe

Accesses Microsoft Outlook accounts 1 TTPs 1 IoCs

collection

Email Collection

T1114

description	ioc	Process
Key opened	\REGISTRY\USER\S-1-5-21-4246620582-653642754-1174164128-1000\Software\Microsoft\Office\Outlook\OMI Account Manager\Accounts	winlogon.exe

Adds Run key to start application 2 TTPs 2 IoCs

persistence

Registry Run Keys / Startup Folder

T1060

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\USER\S-1-5-21-4246620582-653642754-1174164128-1000\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\Winlogon = "C:\\Users\\Admin\\AppData\\Roaming\\SubFolder\\SubFolder\\winlogon.exe"	winlogon.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\Winlogon = "C:\\Users\\Admin\\AppData\\Roaming\\SubFolder\\SubFolder\\winlogon.exe"	winlogon.exe

Suspicious use of SetThreadContext 3 IoCs

description	pid	Process	procid_target
PID 2572 set thread context of 100	2572	winlogon.exe	84
PID 100 set thread context of 4260	100	winlogon.exe	86
PID 100 set thread context of 864	100	winlogon.exe	90

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

System Information Discovery
T1082

Program crash 1 IoCs

pid	pid_target	Process	procid_target
3224	4260	WerFault.exe	86

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
100	winlogon.exe

Suspicious use of WriteProcessMemory 26 IoCs

description	pid	Process	procid_target
PID 1276 wrote to memory of 2572	1276	b3de5859d79cba761fb3f22ffb4f2c674452d4ddedc2732b9a1bc0fbed0926b9.exe	83
PID 1276 wrote to memory of 2572	1276	b3de5859d79cba761fb3f22ffb4f2c674452d4ddedc2732b9a1bc0fbed0926b9.exe	83
PID 2572 wrote to memory of 100	2572	winlogon.exe	84
PID 2572 wrote to memory of 100	2572	winlogon.exe	84
PID 2572 wrote to memory of 100	2572	winlogon.exe	84
PID 2572 wrote to memory of 100	2572	winlogon.exe	84
PID 2572 wrote to memory of 100	2572	winlogon.exe	84
PID 2572 wrote to memory of 100	2572	winlogon.exe	84
PID 2572 wrote to memory of 100	2572	winlogon.exe	84
PID 2572 wrote to memory of 100	2572	winlogon.exe	84
PID 100 wrote to memory of 4260	100	winlogon.exe	86
PID 100 wrote to memory of 4260	100	winlogon.exe	86
PID 100 wrote to memory of 4260	100	winlogon.exe	86
PID 100 wrote to memory of 4260	100	winlogon.exe	86
PID 100 wrote to memory of 4260	100	winlogon.exe	86
PID 100 wrote to memory of 4260	100	winlogon.exe	86
PID 100 wrote to memory of 4260	100	winlogon.exe	86
PID 100 wrote to memory of 4260	100	winlogon.exe	86
PID 100 wrote to memory of 864	100	winlogon.exe	90
PID 100 wrote to memory of 864	100	winlogon.exe	90
PID 100 wrote to memory of 864	100	winlogon.exe	90
PID 100 wrote to memory of 864	100	winlogon.exe	90
PID 100 wrote to memory of 864	100	winlogon.exe	90
PID 100 wrote to memory of 864	100	winlogon.exe	90
PID 100 wrote to memory of 864	100	winlogon.exe	90
PID 100 wrote to memory of 864	100	winlogon.exe	90

C:\Users\Admin\AppData\Local\Temp\b3de5859d79cba761fb3f22ffb4f2c674452d4ddedc2732b9a1bc0fbed0926b9.exe
"C:\Users\Admin\AppData\Local\Temp\b3de5859d79cba761fb3f22ffb4f2c674452d4ddedc2732b9a1bc0fbed0926b9.exe"
1⤵
- Checks computer location settings
- Suspicious use of WriteProcessMemory
PID:1276
- C:\Users\Admin\AppData\Roaming\SubFolder\SubFolder\winlogon.exe
  "C:\Users\Admin\AppData\Roaming\SubFolder\SubFolder\winlogon.exe"
  2⤵
  - Executes dropped EXE
  - Adds Run key to start application
  - Suspicious use of SetThreadContext
  - Suspicious use of WriteProcessMemory
  PID:2572
- - C:\Users\Admin\AppData\Roaming\Microsoft\winlogon.exe
    "C:\Users\Admin\AppData\Roaming\Microsoft\winlogon.exe"
    3⤵
    - Executes dropped EXE
    - Suspicious use of SetThreadContext
    - Suspicious use of SetWindowsHookEx
    - Suspicious use of WriteProcessMemory
    PID:100
  - - C:\Users\Admin\AppData\Roaming\Microsoft\winlogon.exe
      /scomma "C:\Users\Admin\AppData\Local\Temp\w7SLct27x4.ini"
      4⤵
      Executes dropped EXE
      PID:4260
    - - C:\Windows\SysWOW64\WerFault.exe
        
        C:\Windows\SysWOW64\WerFault.exe -u -p 4260 -s 80
        5⤵
        Program crash
        
        PID:3224
  - - C:\Users\Admin\AppData\Roaming\Microsoft\winlogon.exe
      /scomma "C:\Users\Admin\AppData\Local\Temp\XpVkMr3Plo.ini"
      4⤵
      Executes dropped EXE
      Accesses Microsoft Outlook accounts
      PID:864

C:\Windows\SysWOW64\WerFault.exe
C:\Windows\SysWOW64\WerFault.exe -pss -s 444 -p 4260 -ip 4260
1⤵
PID:4424

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Registry Run Keys / Startup Folder

1

T1060

Privilege Escalation

Defense Evasion

Modify Registry

1

T1112

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\Roaming\Microsoft\winlogon.exe

Filesize
4KB

MD5
e1190859ab4f21e58d1873afc1b3cff2

SHA1
50d4f9f444dba70b9918c4b812b5d9a098e0f867

SHA256
9b6f8344738cd1b954066a8099333dfa46c360700d8113312e8f1f6f22afcb73

SHA512
f3924e6b6002e9122c9465d23ff5a574268800078e9fe6011e0d62dca6113ffaf786fa46338a02288d8059e09ef0e79ac96d004dacabcb708291cf4376294a38

Download Submit
C:\Users\Admin\AppData\Roaming\Microsoft\winlogon.exe

Filesize
4KB

MD5
e1190859ab4f21e58d1873afc1b3cff2

SHA1
50d4f9f444dba70b9918c4b812b5d9a098e0f867

SHA256
9b6f8344738cd1b954066a8099333dfa46c360700d8113312e8f1f6f22afcb73

SHA512
f3924e6b6002e9122c9465d23ff5a574268800078e9fe6011e0d62dca6113ffaf786fa46338a02288d8059e09ef0e79ac96d004dacabcb708291cf4376294a38

Download Submit
C:\Users\Admin\AppData\Roaming\Microsoft\winlogon.exe

Filesize
4KB

MD5
e1190859ab4f21e58d1873afc1b3cff2

SHA1
50d4f9f444dba70b9918c4b812b5d9a098e0f867

SHA256
9b6f8344738cd1b954066a8099333dfa46c360700d8113312e8f1f6f22afcb73

SHA512
f3924e6b6002e9122c9465d23ff5a574268800078e9fe6011e0d62dca6113ffaf786fa46338a02288d8059e09ef0e79ac96d004dacabcb708291cf4376294a38

Download Submit
C:\Users\Admin\AppData\Roaming\Microsoft\winlogon.exe

Filesize
4KB

MD5
e1190859ab4f21e58d1873afc1b3cff2

SHA1
50d4f9f444dba70b9918c4b812b5d9a098e0f867

SHA256
9b6f8344738cd1b954066a8099333dfa46c360700d8113312e8f1f6f22afcb73

SHA512
f3924e6b6002e9122c9465d23ff5a574268800078e9fe6011e0d62dca6113ffaf786fa46338a02288d8059e09ef0e79ac96d004dacabcb708291cf4376294a38

Download Submit
C:\Users\Admin\AppData\Roaming\SubFolder\SubFolder\winlogon.exe

Filesize
360KB

MD5
5d0c3fed471d11d19e9dc10103bead3e

SHA1
865d8950c66519d206261926538e40073a252954

SHA256
b3de5859d79cba761fb3f22ffb4f2c674452d4ddedc2732b9a1bc0fbed0926b9

SHA512
76285d896b45586660456b646910a822203325d57789abfb4619974620f18c370cdd9988331f8fe1283d0c16431d1c46aeae7e9fe2e55537d1ef7a041bac8f50

Download Submit
C:\Users\Admin\AppData\Roaming\SubFolder\SubFolder\winlogon.exe

Filesize
360KB

MD5
5d0c3fed471d11d19e9dc10103bead3e

SHA1
865d8950c66519d206261926538e40073a252954

SHA256
b3de5859d79cba761fb3f22ffb4f2c674452d4ddedc2732b9a1bc0fbed0926b9

SHA512
76285d896b45586660456b646910a822203325d57789abfb4619974620f18c370cdd9988331f8fe1283d0c16431d1c46aeae7e9fe2e55537d1ef7a041bac8f50

Download Submit
memory/100-145-0x0000000000400000-0x0000000000442000-memory.dmp

Filesize
264KB

Download
memory/100-139-0x0000000000400000-0x0000000000442000-memory.dmp

Filesize
264KB

Download
memory/100-137-0x0000000000400000-0x0000000000442000-memory.dmp

Filesize
264KB

Download
memory/100-160-0x0000000000400000-0x0000000000442000-memory.dmp

Filesize
264KB

Download
memory/100-151-0x0000000000400000-0x0000000000442000-memory.dmp

Filesize
264KB

Download
memory/864-157-0x0000000000400000-0x000000000041F000-memory.dmp

Filesize
124KB

Download
memory/864-159-0x0000000000400000-0x000000000041F000-memory.dmp

Filesize
124KB

Download
memory/864-153-0x0000000000400000-0x000000000041F000-memory.dmp

Filesize
124KB

Download
memory/864-158-0x0000000000400000-0x000000000041F000-memory.dmp

Filesize
124KB

Download
memory/864-156-0x0000000000400000-0x000000000041F000-memory.dmp

Filesize
124KB

Download
memory/1276-132-0x00007FFC413A0000-0x00007FFC41DD6000-memory.dmp

Filesize
10.2MB

Download
memory/2572-136-0x00007FFC413A0000-0x00007FFC41DD6000-memory.dmp

Filesize
10.2MB

Download

Analysis

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