agenttesla | 4c482b22456df2e37106d59a8afeccdeb736ee89b13b3de6968acee2f3ce9f25

General

Target
01_file.exe
Size 1.8MB
Sample201114-lsqx99ptfx
SHA256 4c482b22456df2e37106d59a8afeccdeb736ee89b13b3de6968acee2f3ce9f25
MD5 6c4a9f7c8893254e10bc2217cec26aef
SHA1 73a0452fbc80e1d7782888e28c46e49d7e01ebd1
SHA512 0266942220119efe2241b66604c51cf6e077118a4eb4904f8f4a3dbcd59067a325f416fb0dca8ef965e6749aae4e49eb1fb2e159919b6e513e89a599cb775491
MD5 SHA1 SHA512

Score

10^/10

agenttesla evasion keylogger persistence spyware stealer trojan

Malware Config

Extracted

Family

agenttesla

Credentials

Protocol
smtp
Host
mail.hkcostarn.com
Port
587
Username
[email protected]
Password
result@123

Signatures

AgentTesla
Agent Tesla is a remote access tool (RAT) written in visual basic.
keylogger trojan stealer spyware agenttesla

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-1-5-21-1985363256-3005190890-1182679451-1000\Software\Microsoft\Windows NT\CurrentVersion\Winlogon\shell = "explorer.exe,\"C:\\Users\\Admin\\AppData\\Local\\Temp\\01_file.exe\""	01_file.exe

AgentTesla Payload 2 IoCs

resource	yara_rule
behavioral2/memory/1364-7-0x0000000000400000-0x000000000043C000-memory.dmp	family_agenttesla
behavioral2/memory/1364-8-0x0000000000437AEE-mapping.dmp	family_agenttesla

Looks for VirtualBox Guest Additions in registry 2 TTPs
evasion

Query Registry
T1012

Virtualization/Sandbox Evasion
T1497
Looks for VMWare Tools registry key 2 TTPs
evasion

Query Registry
T1012

Virtualization/Sandbox Evasion
T1497

Checks BIOS information in registry 2 TTPs 2 IoCs

BIOS information is often read in order to detect sandboxing environments.

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\SystemBiosVersion	01_file.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\VideoBiosVersion	01_file.exe

Drops startup file 2 IoCs

description	ioc	Process
File created	C:\Users\Admin\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup\01_file.exe	01_file.exe
File opened for modification	C:\Users\Admin\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup\01_file.exe	01_file.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-1-5-21-1985363256-3005190890-1182679451-1000\Software\Microsoft\Windows\CurrentVersion\Run\01_file.exe = "C:\\Users\\Admin\\AppData\\Local\\Temp\\01_file.exe"	01_file.exe
Set value (str)	\REGISTRY\USER\S-1-5-21-1985363256-3005190890-1182679451-1000\Software\Microsoft\Windows\CurrentVersion\Run\<Unknown> = "C:\\Users\\Admin\\AppData\\Local\\Temp\\01_file.exe"	01_file.exe

Looks up external IP address via web service 2 IoCs

Uses a legitimate IP lookup service to find the infected system's external IP.

flow	ioc
17	api.ipify.org
16	api.ipify.org

Maps connected drives based on registry 3 TTPs 2 IoCs

Disk information is often read in order to detect sandboxing environments.

Query Registry

T1012

Peripheral Device Discovery

T1120

System Information Discovery

T1082

description	ioc	Process
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Services\Disk\Enum	01_file.exe
Key value queried	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Services\Disk\Enum\0	01_file.exe

Suspicious use of NtSetInformationThreadHideFromDebugger 10 IoCs

pid	Process
640	01_file.exe
640	01_file.exe
640	01_file.exe
640	01_file.exe
640	01_file.exe
640	01_file.exe
640	01_file.exe
640	01_file.exe
640	01_file.exe
640	01_file.exe

Suspicious use of SetThreadContext 1 IoCs

description	pid	Process	procid_target
PID 640 set thread context of 1364	640	01_file.exe	77

Program crash 1 IoCs

pid	pid_target	Process	procid_target
3368	640	WerFault.exe	67

Suspicious behavior: EnumeratesProcesses 19 IoCs

pid	Process
640	01_file.exe
640	01_file.exe
640	01_file.exe
1364	regsvcs.exe
1364	regsvcs.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe
3368	WerFault.exe

Suspicious use of AdjustPrivilegeToken 5 IoCs

description	pid	Process
Token: SeDebugPrivilege	640	01_file.exe
Token: SeDebugPrivilege	1364	regsvcs.exe
Token: SeRestorePrivilege	3368	WerFault.exe
Token: SeBackupPrivilege	3368	WerFault.exe
Token: SeDebugPrivilege	3368	WerFault.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
1364	regsvcs.exe

Suspicious use of WriteProcessMemory 8 IoCs

description	pid	Process	procid_target
PID 640 wrote to memory of 1364	640	01_file.exe	77
PID 640 wrote to memory of 1364	640	01_file.exe	77
PID 640 wrote to memory of 1364	640	01_file.exe	77
PID 640 wrote to memory of 1364	640	01_file.exe	77
PID 640 wrote to memory of 1364	640	01_file.exe	77
PID 640 wrote to memory of 1364	640	01_file.exe	77
PID 640 wrote to memory of 1364	640	01_file.exe	77
PID 640 wrote to memory of 1364	640	01_file.exe	77

C:\Users\Admin\AppData\Local\Temp\01_file.exe
"C:\Users\Admin\AppData\Local\Temp\01_file.exe"
1⤵
- Modifies WinLogon for persistence
- Checks BIOS information in registry
- Drops startup file
- Adds Run key to start application
- Maps connected drives based on registry
- Suspicious use of NtSetInformationThreadHideFromDebugger
- Suspicious use of SetThreadContext
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:640
- C:\Windows\Microsoft.NET\Framework\v4.0.30319\regsvcs.exe
  "C:\Windows\Microsoft.NET\Framework\v4.0.30319\regsvcs.exe"
  2⤵
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of SetWindowsHookEx
  PID:1364
- C:\Windows\SysWOW64\WerFault.exe
  C:\Windows\SysWOW64\WerFault.exe -u -p 640 -s 1296
  2⤵
  - Program crash
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  PID:3368