isrstealer | 52e12872c56fe3448ecfbaacb3ef19f4c5dda64697754dadcf16a1e1e0816a3c

General

Target

WowbeezFan 5.2.3.exe
Size

707KB
MD5

be1f1639c3fc7332a7300920c0c26bd5
SHA1

39e46d7f8293b4f37624b24ff18eda4b04badede
SHA256

233592aca1140c5e5a405dcc63fd94ecc671ce418132ee971dc0153becc5a4bb
SHA512

4115a651908a6f8b8e482aade1eb2cf40288962316075ee8af6f50c0b14b6c604bdde9c11198213e02d6d368b0adf9d5a5999a4b7ee4ac459ce73e015657a89d
SSDEEP

12288:JuL6yZH3QqgvGmE9oExlzyceKLzpf4AGv+NmBfiITG9q:JuLrJRlfb7Aim

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/2436-17-0x0000000000400000-0x0000000000435000-memory.dmp	family_isrstealer
behavioral1/memory/2436-13-0x0000000000400000-0x0000000000435000-memory.dmp	family_isrstealer
behavioral1/memory/2436-32-0x0000000000400000-0x0000000000435000-memory.dmp	family_isrstealer

Isrstealer family
isrstealer

Executes dropped EXE 2 IoCs

pid	Process
2436	taskmgr.exe
2660	taskmgr.exe

Loads dropped DLL 3 IoCs

pid	Process
2468	WowbeezFan 5.2.3.exe
2468	WowbeezFan 5.2.3.exe
2436	taskmgr.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 2468 set thread context of 2436	2468	WowbeezFan 5.2.3.exe	31
PID 2436 set thread context of 2660	2436	taskmgr.exe	32

UPX packed file 5 IoCs

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

upx

resource	yara_rule
behavioral1/memory/2660-26-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral1/memory/2660-29-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral1/memory/2660-30-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral1/memory/2660-31-0x0000000000400000-0x0000000000453000-memory.dmp	upx
behavioral1/memory/2660-37-0x0000000000400000-0x0000000000453000-memory.dmp	upx

System Location Discovery: System Language Discovery 1 TTPs 3 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	WowbeezFan 5.2.3.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	taskmgr.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	taskmgr.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
2436	taskmgr.exe

Suspicious use of WriteProcessMemory 17 IoCs

description	pid	Process	procid_target
PID 2468 wrote to memory of 2436	2468	WowbeezFan 5.2.3.exe	31
PID 2468 wrote to memory of 2436	2468	WowbeezFan 5.2.3.exe	31
PID 2468 wrote to memory of 2436	2468	WowbeezFan 5.2.3.exe	31
PID 2468 wrote to memory of 2436	2468	WowbeezFan 5.2.3.exe	31
PID 2468 wrote to memory of 2436	2468	WowbeezFan 5.2.3.exe	31
PID 2468 wrote to memory of 2436	2468	WowbeezFan 5.2.3.exe	31
PID 2468 wrote to memory of 2436	2468	WowbeezFan 5.2.3.exe	31
PID 2468 wrote to memory of 2436	2468	WowbeezFan 5.2.3.exe	31
PID 2436 wrote to memory of 2660	2436	taskmgr.exe	32
PID 2436 wrote to memory of 2660	2436	taskmgr.exe	32
PID 2436 wrote to memory of 2660	2436	taskmgr.exe	32
PID 2436 wrote to memory of 2660	2436	taskmgr.exe	32
PID 2436 wrote to memory of 2660	2436	taskmgr.exe	32
PID 2436 wrote to memory of 2660	2436	taskmgr.exe	32
PID 2436 wrote to memory of 2660	2436	taskmgr.exe	32
PID 2436 wrote to memory of 2660	2436	taskmgr.exe	32
PID 2436 wrote to memory of 2660	2436	taskmgr.exe	32

C:\Users\Admin\AppData\Local\Temp\WowbeezFan 5.2.3.exe
"C:\Users\Admin\AppData\Local\Temp\WowbeezFan 5.2.3.exe"
1⤵
- Loads dropped DLL
- Suspicious use of SetThreadContext
- System Location Discovery: System Language Discovery
- Suspicious use of WriteProcessMemory
PID:2468
- C:\Users\Admin\AppData\Roaming\taskmgr.exe
  C:\Users\Admin\AppData\Roaming\taskmgr.exe
  2⤵
  - 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:2436
- - C:\Users\Admin\AppData\Roaming\taskmgr.exe
    /scomma "C:\Users\Admin\AppData\Local\Temp\a30ZJf3vv2.ini"
    3⤵
    - Executes dropped EXE
    - System Location Discovery: System Language Discovery
    PID:2660

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 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

\Users\Admin\AppData\Roaming\taskmgr.exe

Filesize
2KB

MD5
86b6f78ab4571ae949f8a0d9757eadfe

SHA1
fee56dc91bb2f495b1d1a3e89d5b2b21eb5194f7

SHA256
4b8f2769a6847b7a09952010e03161be2033f699dfa26e41324a6ba7c936ca69

SHA512
3c11270e4507cd4ef274d837c02b66370c37af82a3afbf28d1bedf040c87c70972a981edf15ae8312c3d237234a8018c3c4ffd68ff4c852bdd484b5ea4297869

Download Submit
memory/2436-12-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/2436-13-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/2436-32-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/2436-11-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/2436-17-0x0000000000400000-0x0000000000435000-memory.dmp

Filesize
212KB

Download
memory/2436-15-0x000000007EFDE000-0x000000007EFDF000-memory.dmp

Filesize
4KB

Download
memory/2468-21-0x0000000074FD0000-0x000000007557B000-memory.dmp

Filesize
5.7MB

Download
memory/2468-0-0x0000000074FD1000-0x0000000074FD2000-memory.dmp

Filesize
4KB

Download
memory/2468-2-0x0000000074FD0000-0x000000007557B000-memory.dmp

Filesize
5.7MB

Download
memory/2468-1-0x0000000074FD0000-0x000000007557B000-memory.dmp

Filesize
5.7MB

Download
memory/2660-26-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/2660-29-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/2660-30-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/2660-31-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download
memory/2660-37-0x0000000000400000-0x0000000000453000-memory.dmp

Filesize
332KB

Download

Analysis

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