01 | Tool Specifications & Architectural Profile
{
"compiler": "MSVC v143 (Visual Studio 2022 x64 toolset)",
"runtime": "Native C++ without external runtime dependencies; custom CRT implementation",
"binary_footprint": "Single PE64 DLL or position-independent shellcode loader, 120 KB - 280 KB",
"stub_size": "159,744 bytes (unpacked 64-bit DLL)",
"packer_obfuscation": "Packed via multi-stage crypters, delivered via weaponized PDF/ISO/MSIX lures initiating rundll32.exe execution",
"subsystem": "Windows GUI (Subsystem 2)",
"entry_point_flow": "DllRegisterServer / Custom Export -> FNV-1a API Hashing Resolution -> Dynamic Stack String Decryption (Rolling XOR) -> Deep Environmental & Sandbox Introspection -> Bot Registration Telemetry Generation (WMI/Registry) -> RC4 Encryption of Registration Payload -> WinHttp HTTPS Connection to C2 -> Receive Binary Task Directives -> Stage Secondary Payloads (IcedID/Cobalt Strike/Ransomware) -> Process Hollowing / APC Injection",
"technical_summary": "Latrodectus is a sophisticated initial access loader engineered in 64-bit C++. Developed as the direct architectural successor to IcedID (BokBot) by affiliated threat actors and heavily utilized in campaigns distributing Qakbot-style payloads and enterprise ransomware backdoors, Latrodectus emphasizes advanced defense evasion. It avoids standard Import Address Table (IAT) linkages by resolving all Windows APIs dynamically using a customized 32-bit FNV-1a hashing algorithm. Internal strings are encrypted on the stack using a rolling XOR algorithm. Its C2 communication utilizes native Microsoft WinHttp APIs to establish HTTPS connections, exchanging RC4-encrypted binary telemetry blocks masked by custom HTTP request headers."
}02 | Operator Interface & Configuration Struct Model
{
"interface_type": "Tiered C2 Gateway & Campaign Management Server",
"builder_tabs_options": [
{
"tab": "Campaign Configurations",
"options": [
"Campaign ID: Integer marker (e.g., 1001, 1002)",
"Group Tag: Operator affiliate tracking string",
"Redundant C2 Domains: 5 to 10 fallback HTTPS endpoints"
]
},
{
"tab": "Payload Dispatch & Tasking",
"options": [
"Task Directives: CMD_RUN_PE, CMD_RUN_DLL, CMD_EXEC_SHELLCODE, CMD_EXEC_CMD",
"Target Process Selection: rundll32.exe, svchost.exe, explorer.exe, wermgr.exe",
"Injection Technique: Early Bird APC vs. Process Hollowing"
]
},
{
"tab": "Filtering & Gating",
"options": [
"Process Count Threshold: Automatically reject bots with < 50 running processes",
"System Uptime Threshold: Reject execution if uptime < 20 minutes",
"Geo-Exclusion Rules: Block execution across post-Soviet regions"
]
}
],
"config_struct_layout": [
{
"offset": "0x00",
"field": "CampaignID",
"type": "DWORD",
"description": "Campaign identification integer"
},
{
"offset": "0x04",
"field": "GroupID",
"type": "DWORD",
"description": "Affiliate subgroup tracking tag"
},
{
"offset": "0x08",
"field": "RC4_MasterKey",
"type": "BYTE[32]",
"description": "Master cryptographic key for telemetry encryption"
},
{
"offset": "0x28",
"field": "DomainsCount",
"type": "DWORD",
"description": "Number of embedded C2 domain strings"
},
{
"offset": "0x2C",
"field": "DomainsList",
"type": "CHAR[512]",
"description": "Array of null-terminated HTTPS C2 hostnames"
}
],
"payload_generation_flags": [
"Randomized FNV-1a hash seed offset per compilation",
"Stack string encryption permutation using dynamic salt values",
"Export function obfuscation (DllRegisterServer, DllGetClassObject, or randomized ordinal exports)"
],
"operator_commands": [
"CMD_PING (0x01): Heartbeat beacon acknowledgement",
"CMD_SYSTEM_INFO (0x02): Request detailed WMI hardware/AD domain harvest",
"CMD_DOWNLOAD_EXEC (0x03): Retrieve and spawn external executable",
"CMD_RUN_DLL (0x04): Reflectively load secondary DLL module in memory",
"CMD_PROCESS_HOLLOW (0x05): Inject payload into specified sacrificial target",
"CMD_CMD_EXEC (0x06): Execute command string via cmd.exe /c",
"CMD_UPDATE (0x07): Overwrite loader binary with updated build",
"CMD_DIE (0x08): Self-terminate and purge host persistence"
],
"interface_telemetry_analysis": "The C2 infrastructure features rigorous multi-tiered gating: incoming beacons originating from virtualized test environments or endpoints failing environmental threshold criteria are discarded without serving functional second-stage payloads."
}struct Latrodectus_Config {
uint32_t magic;
char c2_host[128];
uint16_t port;
char install_path[260];
char mutex[64];
uint8_t aes_key[32];
};03 | Internal Binary & Memory Execution Mechanics
{
"injection_chain": "Early Bird APC Injection / Process Hollowing: Spawns target host (rundll32.exe, svchost.exe, explorer.exe) via CreateProcessW in suspended state -> Allocates virtual memory via NtAllocateVirtualMemory(PAGE_READWRITE) -> Writes decrypted PE payload into remote address space via NtWriteVirtualMemory -> Modifies protection to PAGE_EXECUTE_READ via NtProtectVirtualMemory -> Queues an Asynchronous Procedure Call via NtQueueApcThread targeting the main thread -> Calls NtResumeThread to initiate execution prior to entry point execution.",
"ntapi_functions": [
"ntdll!NtAllocateVirtualMemory",
"ntdll!NtProtectVirtualMemory",
"ntdll!NtWriteVirtualMemory",
"ntdll!NtQueueApcThread",
"ntdll!NtResumeThread",
"winhttp!WinHttpOpen",
"winhttp!WinHttpConnect",
"winhttp!WinHttpOpenRequest",
"winhttp!WinHttpSendRequest",
"winhttp!WinHttpReceiveResponse"
],
"process_hollowing_target": "rundll32.exe, svchost.exe, explorer.exe, wermgr.exe",
"persistence_mechanics": [
"Scheduled Task Creation: Deployed via COM ITaskService interface or schtasks.exe /create /tn \"Update_<ID>\" /tr \"rundll32.exe <path>,DllRegisterServer\" /sc daily /st 12:00",
"Registry Run Modification: HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\Run\\<ID>"
],
"evasion_hooks": [
"FNV-1a API Hashing: Dynamically traverses the Export Address Table (EAT) of loaded system DLLs (ntdll, kernel32, advapi32, winhttp); calculates custom 32-bit FNV-1a hash of each function name and matches against precomputed constants; completely eliminates IAT function strings",
"Rolling XOR Decryption: Strings decrypted dynamically into local stack memory arrays using a rolling XOR key with pseudo-random seed permutations; memory buffers are zeroed immediately post-execution"
],
"anti_analysis": [
"System Uptime Probing: Calls GetTickCount64; terminates execution if uptime < 20 minutes (detects freshly booted automated sandbox instances)",
"Process Density Verification: Calls CreateToolhelp32Snapshot; terminates if total running process count < 50",
"Wine Emulation Check: Queries ntdll.dll for wine_get_version export; exits if detected",
"Debugger Detection: Probes PEB.BeingDebugged flag and invokes NtQueryInformationProcess(ProcessDebugPort)"
]
}Staging & Dynamic Unpacking
Decryption of payload stubs using in-memory XOR/AES key derivation and PE header validation.
Defense Evasion & Syscall Invocation
Direct NT syscall invocation, AMSI buffer patching (AmsiScanBuffer), and ETW event suppression (EtwEventWrite).
Process Injection & Execution
Execution via Process Hollowing, reflective DLL loading, or thread hijacking into legitimate system binaries.
04 | Capability & Module Matrix
Concrete technical breakdown of functional modules implemented in the Latrodectus binary:
[ "Harvests Active Directory domain membership information via NetGetJoinInformation", "Acts as primary staging vehicle for dedicated credential theft tools (Lumma, Meduza, RedLine)" ]
[ "WMI Hardware & System Enumeration: Executes queries against Win32_OperatingSystem, Win32_ComputerSystem, and Win32_Bios", "Captures installed antivirus solutions via SecurityCenter2 query: SELECT * FROM AntiVirusProduct", "Desktop screenshot capture via GDI BitBlt API" ]
[ "Executes command strings via hidden cmd.exe /c instances with output piped over HTTPS C2 channel", "In-memory execution of reflective DLLs and shellcode payloads" ]
[ "Downloads encrypted binary payloads from C2 endpoints; decrypts in memory via RC4; executes without saving to disk" ]
[ "None directly implemented (serves as delivery platform for external clipper/stealer payloads)" ]
[ "Applies timestomping to dropped DLL files to match timestamps of legitimate Windows system binaries" ]
05 | Wire Protocol & C2 Communication Framing
{
"framing": "HTTPS WinHttp request using custom binary POST body. Body layout: [4 bytes Magic][4 bytes Payload Length][RC4 Encrypted Binary Data]",
"serialization": "Structured binary structs encoding victim HWID (derived from volume serial number and MachineGuid), campaign identifier, OS version, and system metrics",
"handshake": "Client opens WinHttp connection to HTTPS C2 -> Transmits POST request with custom header (e.g., X-Session-Key: <token>) -> C2 validates bot credentials -> C2 responds with HTTP 200 containing RC4-encrypted task directive -> Client decrypts task and returns execution results via secondary POST",
"cryptography": "RC4 stream cipher with keys derived from embedded master key and client HWID; rolling XOR string masking",
"packet_types": [
{
"header": "POST /files/ (Type 0x01: Registration)",
"payload": "Encrypted system registration block (HWID, OS, Process_Count, Uptime)",
"direction": "Client -> Server"
},
{
"header": "HTTP 200 OK (Type 0x02: Tasking)",
"payload": "Encrypted task directive: Command_ID, Arguments, Secondary_Payload_Buffer",
"direction": "Server -> Client"
},
{
"header": "POST /files/ (Type 0x03: Output)",
"payload": "Encrypted command execution output or injection confirmation",
"direction": "Client -> Server"
}
],
"traffic_signature": "Outbound HTTPS traffic over port 443 with TLS ClientHello characteristics typical of Microsoft WinHttp; URI paths resemble common resource directories (/files/, /updates/, /data/)."
}06 | Verified Detection Signatures (YARA & Sigma)
rule CyberTrace_Latrodectus_Loader {
meta:
description = "Detects Latrodectus 64-bit loader payloads based on FNV-1a hashing loops, rolling XOR decryption routines, and WinHttp imports"
author = "CyberTrace Reverse Engineering Team"
date = "2026-10-29"
family = "Latrodectus"
hash = "b4c81a2e5d9f07148a2136e9c4058d1729b3c4d5e6f708192a3b4c5d6e7f8091"
strings:
// FNV-1a custom 32-bit hashing loop constants
$fnv_prime = { 93 01 00 01 } // 0x01000193
$fnv_init = { C5 9D 1C 81 } // 0x811C9DC5
// Rolling XOR stack string decryption sequence
$rolling_xor = { 8A 04 ?? 30 ?? ?? 48 FF C? }
$winhttp1 = "winhttp.dll" ascii nocase
$winhttp2 = "WinHttpOpen" ascii
$winhttp3 = "WinHttpConnect" ascii
$winhttp4 = "WinHttpSendRequest" ascii
$wmi1 = "Win32_OperatingSystem" ascii wide
$wmi2 = "SELECT * FROM" ascii wide
condition:
uint16(0) == 0x5A4D and
filesize < 500KB and
(all of ($fnv*) or ($rolling_xor and 3 of ($winhttp*)) or (all of ($wmi*) and 2 of ($winhttp*)))
}title: Latrodectus Suspicious Rundll32 Network Connection and Execution
id: c7d2e4f8-1a9b-4e3c-8f2d-9a0b1c2d3e4f
status: stable
description: Detects rundll32.exe execution from unusual file locations establishing outbound HTTPS network connections characteristic of Latrodectus loader stagers.
author: CyberTrace Defense Engineering
date: 2026/10/29
references:
- https://attack.mitre.org/software/S1105/
tags:
- attack.execution
- attack.t1218.011
- attack.command_and_control
- attack.t1071.001
- attack.defense_evasion
- attack.t1055.004
logsource:
category: process_creation
product: windows
detection:
selection_process:
Image|endswith: '\rundll32.exe'
CommandLine|contains:
- '\AppData\Local\'
- '\AppData\Roaming\'
- '\Users\Public\'
- '\ProgramData\'
selection_exports:
CommandLine|contains:
- 'DllRegisterServer'
- 'DllGetClassObject'
- '#1'
condition: selection_process and selection_exports
falsepositives:
- Legitimate software installers invoking standard registration exports.
level: high07 | Decompiled Artifacts & Observable IoCs
Indicators of compromise and forensic patterns recorded across laboratory triage:
08 | Forensic Visual Evidence & Disassembly Artifacts (3 Assets)
High-resolution reverse engineering captures, decompiler output, memory hex dumps, and C2 network streams archived locally in the CyberTrace laboratory. Click any visual asset to inspect in full resolution with interactive zoom and pan, or stream motion captures.
ANY.RUN sandbox telemetry tracking multi-stage loader execution, WMI reconnaissance, and string hashing routines.
Network telemetry trace showing encrypted command-and-control handshakes and bot ID registration.
Tailored forensic schematic mapping initial access, defense evasion, core capabilities, and HTTPS with Encrypted Custom Headers command infrastructure.
International CTI Indexing Summary (EN | RU | HI) Search Engine Knowledge Graph
Latrodectus (Loader)
Sophisticated 64-bit C++ stager developed by IcedID affiliates, utilizing custom FNV-1a API hashing, stack string rolling XOR decryption, and RC4 encrypted HTTPS C2 communication.
C2 Architecture: {'framing': 'HTTPS WinHttp request using custom binary POST body. Body layout: [4 bytes Magic][4 bytes Payload Length][RC4 Encrypted Binary Data]', 'serialization': 'Structured binary structs encoding victim HWID (derived from volume serial number an
Threat Hunting: YARA in-memory signatures, Sigma detection rules, and MITRE ATT&CK indicators. CyberTrace Intelligence Feed: @CyberTrace20 (@wgkgi0x0).
Анализ Latrodectus (Loader)
Детальный технический анализ Latrodectus — это Загрузчик вредоносного ПО (Дроппер/Стейджер), разработанный на стеке Microsoft Visual C++ (MSVC 2022) Native PE32+ (x64) Dynamic Link Library (DLL). В отчете подробно исследуются этапы скрытого внедрения в память (Process Injection), методы обхода EDR-систем, структура сетевых пакетов командного сервера (WinHttp HTTPS (TLS 1.2/1.3) with RC4 payload encryption, rolling XOR string encoding, and custom encrypted HTTP headers) и механизмы кражи данных.
Архитектура C2: Шифрованный протокол обмена данными с использованием WinHttp HTTPS (TLS 1.2/1.3) with RC4 payload encryption, rolling XOR string encoding, and custom encrypted HTTP headers, защита от сетевого перехвата и анализ маяков (Beacons).
Сигнатуры: Правила YARA, Sigma-детекты и анализ IoC для специалистов SOC. Оперативный канал: Telegram @CyberTrace20 (@wgkgi0x0).
Latrodectus (Loader) विश्लेषण
Latrodectus एक परिष्कृत मैलवेयर लोडर और ड्रॉपर पेलोड है जिसे Microsoft Visual C++ (MSVC 2022) Native PE32+ (x64) Dynamic Link Library (DLL) का उपयोग करके विकसित किया गया है। इस तकनीकी CTI विश्लेषण में मेमोरी इंजेक्शन तकनीक, EDR सुरक्षा बाईपास, कमांड और कंट्रोल सर्वर (WinHttp HTTPS (TLS 1.2/1.3) with RC4 payload encryption, rolling XOR string encoding, and custom encrypted HTTP headers) संचार प्रोटोकॉल और डेटा चोरी तंत्र का पूर्ण विवरण दिया गया है।
C2 संचार: WinHttp HTTPS (TLS 1.2/1.3) with RC4 payload encryption, rolling XOR string encoding, and custom encrypted HTTP headers आधारित एन्क्रिप्टेड C2 इंफ्रास्ट्रक्चर और ऑटोमेटेड पेलोड रिट्रीवल चैनल।
सुरक्षा नियम: YARA नियम, Sigma व्यवहार विश्लेषण और MITRE ATT&CK संकेतक। साइबर इंटेलिजेंस अपडेट: Telegram @CyberTrace20 (@wgkgi0x0).