Parent PID Spoofing

Parent PID Spoofing [T1134.004]

Information

• Name: Parent PID Spoofing

• ID: T1134.004

• Tactics: TA0005, TA0004

• Technique: T1134

Introduction

Parent PID Spoofing (T1134.004) is a sub-technique within the MITRE ATT&CK framework under the broader category of Access Token Manipulation (T1134). This technique involves manipulating the parent process identifier (PID) of a newly spawned malicious process to masquerade as a legitimate process. Attackers leverage Parent PID Spoofing to evade detection, bypass security controls, and blend into the normal operating environment, making attribution and forensic analysis more challenging. By spoofing the parent PID, adversaries can create processes that appear to be initiated by trusted or benign processes, thereby reducing suspicion and increasing persistence capabilities.

Deep Dive Into Technique

Parent PID Spoofing is executed primarily on Windows systems through manipulation of process creation APIs or through direct interaction with system-level functions. The following technical mechanisms and execution methods are typically used:

• Process Creation APIs: Attackers commonly exploit Windows APIs such as CreateProcess, CreateProcessAsUser, and NtCreateUserProcess. These APIs allow attackers to specify attributes of the new process, including the parent process handle, enabling them to select a legitimate-looking parent process.

• Direct System Calls: Adversaries may bypass standard APIs and directly invoke system calls like NtCreateUserProcess or manipulate process attributes directly through lower-level techniques. This approach reduces visibility and detection by traditional monitoring tools that rely on standard API hooking.

• Process Hollowing and Injection: Parent PID Spoofing is frequently combined with other techniques such as process hollowing or injection. Attackers spawn a legitimate process, spoof its parent PID, and then inject malicious code into the created process, making it appear benign to casual inspection.

• Usage of Known Offensive Tools: Tools such as Cobalt Strike, Metasploit, Empire, and custom malware frameworks have built-in capabilities or modules to perform Parent PID Spoofing, simplifying execution for adversaries.

• Manipulation of Handle Inheritance: Attackers can manipulate process handle inheritance, allowing a malicious process to inherit handles from trusted processes, thereby further obfuscating their actions.

When this Technique is Usually Used

Parent PID Spoofing is versatile and can be employed in various attack scenarios and stages, including:

• Initial Access and Execution: Attackers may use spoofing early in the intrusion process to hide the origin of malicious processes spawned from initial compromise vectors, such as phishing payloads or exploited vulnerabilities.

• Privilege Escalation and Defense Evasion: Often combined with privilege escalation techniques, Parent PID Spoofing helps attackers evade endpoint detection and response (EDR) solutions by disguising malicious processes as legitimate system or user-initiated processes.

• Persistence and Lateral Movement: Attackers use Parent PID Spoofing to establish persistent access, making malicious processes appear as legitimate scheduled tasks, services, or user processes, thus blending into regular administrative activities.

• Credential Access and Data Exfiltration: In later stages, attackers may spoof parent processes during credential dumping or data exfiltration to evade detection and attribution.

How this Technique is Usually Detected

Detection of Parent PID Spoofing typically involves a combination of behavioral analysis, monitoring, and anomaly detection methods:

• Process Tree Analysis: Monitoring and analyzing process trees for unusual parent-child relationships can reveal anomalies. For example, unexpected parent-child relationships such as a browser spawning a command shell or PowerShell prompt can indicate spoofing.

• API and Syscall Monitoring: Endpoint Detection and Response (EDR) solutions that hook or monitor API calls (CreateProcess, NtCreateUserProcess) can detect anomalies in process creation attributes, such as unexpected parent handles.

• Event Log Analysis: Windows Security Event Logs (Event ID 4688 - Process Creation) and Sysmon (Event ID 1 - Process Creation) logs can provide visibility into suspicious process relationships and anomalous parent-child associations.

• Behavioral Anomaly Detection Tools: Endpoint protection platforms and SIEM systems can detect anomalies based on historical baselines and behavioral patterns. Unusual process hierarchies or deviations from standard system behavior can trigger alerts.

• Indicators of Compromise (IoCs): Specific IoCs include:

  • Unusual parent-child process relationships (e.g., explorer.exe spawning suspicious processes).

  • Processes with missing or unusual command-line arguments.

  • Processes spawning from unexpected directories or paths.

  • Irregular handle inheritance patterns.

Why it is Important to Detect This Technique

Detecting Parent PID Spoofing is critical due to the significant impacts it can have on system and network security:

• Detection Difficulty and Attribution Challenges: Spoofing parent PIDs complicates incident response and forensic investigations by obscuring the true origin and nature of malicious processes.

• Bypassing Security Controls: Attackers leverage spoofed parent processes to evade detection by endpoint security products, which often rely on known process hierarchies and legitimate relationships.

• Persistence and Long-term Compromise: Failure to detect spoofed processes allows attackers to maintain persistent, long-term access to systems and networks, increasing the potential damage and data loss.

• Facilitation of Advanced Attacks: Parent PID Spoofing is frequently used in conjunction with other sophisticated attack techniques, enabling adversaries to escalate privileges, move laterally, exfiltrate sensitive data, and execute ransomware or destructive payloads.

• Early Detection Reduces Damage: Identifying and mitigating Parent PID Spoofing early in the attack lifecycle significantly limits adversary capabilities, reduces remediation costs, and minimizes potential harm.

Examples

Real-world examples of Parent PID Spoofing demonstrate its effectiveness and frequent use by threat actors:

• Cobalt Strike Framework:

  • Attack Scenario: Adversaries leveraging Cobalt Strike's built-in "Spawn To" feature to spoof legitimate parent processes, such as explorer.exe, to launch malicious payloads.

  • Tools Used: Cobalt Strike Beacon payload.

  • Impact: Successfully bypassed endpoint detection solutions, enabling persistent access and lateral movement within compromised networks.

• Emotet Malware Campaigns:

  • Attack Scenario: Emotet malware utilized parent PID spoofing to disguise malicious processes as legitimate Windows processes, evading endpoint detection solutions and enabling further payload delivery (e.g., TrickBot, Ryuk ransomware).

  • Tools Used: Emotet malware loader, custom scripts.

  • Impact: Enabled widespread infection, credential theft, lateral movement, and eventual ransomware deployment causing significant financial and operational disruption.

• APT29 (Cozy Bear) Operations:

  • Attack Scenario: During sophisticated espionage campaigns, APT29 leveraged parent PID spoofing to disguise malicious processes as legitimate Windows system processes, evading detection and maintaining long-term stealthy persistence.

  • Tools Used: Custom implants, PowerShell scripts, and process injection utilities.

  • Impact: Allowed long-term espionage, data exfiltration, credential harvesting, and lateral movement within targeted government and enterprise networks.

• FIN7 Financially Motivated Group:

  • Attack Scenario: FIN7 used parent PID spoofing to disguise malicious processes as legitimate applications, such as office productivity software, browsers, or system utilities, to evade detection and facilitate lateral movement and data theft.

  • Tools Used: Carbanak malware, custom loaders, and scripts.

  • Impact: Enabled extensive financial fraud, theft of sensitive financial data, and persistent access to compromised networks, resulting in significant financial losses for victim organizations.