hunting-for-process-injection-techniques

name	hunting-for-process-injection-techniques
description	Detect process injection techniques (T1055) including CreateRemoteThread, process hollowing, and DLL injection via Sysmon Event IDs 8 and 10 and EDR process telemetry
domain	cybersecurity
subdomain	threat-hunting
tags	["process-injection","t1055","sysmon","createremotethread","dll-injection","edr","threat-hunting"]
version	1.0
author	mahipal
license	Apache-2.0
d3fend_techniques	["Executable Denylisting","Execution Isolation","File Metadata Consistency Validation","Content Format Conversion","File Content Analysis"]
nist_csf	["DE.CM-01","DE.AE-02","DE.AE-07","ID.RA-05"]

Hunting for Process Injection Techniques

Overview

Process injection (MITRE ATT&CK T1055) allows adversaries to execute code in the address space of another process, enabling defense evasion and privilege escalation. This skill detects injection techniques via Sysmon Event ID 8 (CreateRemoteThread), Event ID 10 (ProcessAccess with suspicious access rights), and analysis of source-target process relationships to distinguish legitimate from malicious injection.

When to Use

• When investigating security incidents that require hunting for process injection techniques
• When building detection rules or threat hunting queries for this domain
• When SOC analysts need structured procedures for this analysis type
• When validating security monitoring coverage for related attack techniques

Detection Gaps & Validation

• Evasions that produce NO Sysmon EID 8: thread hijacking (SetThreadContext), APC injection (QueueUserAPC/NtQueueApcThread, early-bird), mapping injection (NtMapViewOfSection), and process hollowing (NtUnmapViewOfSection + WriteProcessMemory) all skip CreateRemoteThread. They surface only as EID 10 ProcessAccess with PROCESS_VM_WRITE|PROCESS_VM_OPERATION|PROCESS_CREATE_THREAD.
• Userland-hook bypass: indirect/direct syscalls and unhooked NTDLL defeat EDR inline hooks, leaving little or no telemetry — corroborate with EID 7 (ImageLoad of unbacked/floating modules) and kernel ETW.
• EID 10 noise: CSRSS, lsass, AV/EDR, and debuggers legitimately open high-access handles. Tune to cross-process opens where GrantedAccess masks 0x1F0FFF/0x1FFFFF AND the source is unsigned or unusual; treat 0x1000/0x1400 read-only as benign.
• Validate the hunt fires: run Atomic Red Team T1055.001 (process hollowing), T1055.002, and mavinject.exe APC, then confirm EID 8 GrantedAccess and EID 10 access masks are captured.
• FP tuning: allowlist known injector→target pairs (e.g., MsMpEng.exe, vmtoolsd) by signer, not by image name alone.

Prerequisites

• Sysmon installed with Event IDs 8 and 10 enabled
• Process creation logs (Sysmon Event ID 1 or Windows 4688)
• Python 3.8+ with standard library
• JSON-formatted Sysmon event logs

Steps