Windows Registry Forensics – SOC Analyst Cheatsheet

Practical Guide for Live Response & Incident Investigation


Quick Reference: Investigation Priority Matrix

Priority
Registry Area
Investigation Type
Key Questions

CRITICAL

Persistence Keys

Malware/IR

What runs at startup?

CRITICAL

Services

Malware/IR

What malicious services exist?

HIGH

USB/Mounted Devices

Data Exfil

What devices connected?

HIGH

Network Activity

Lateral Movement

What shares accessed?

HIGH

RecentDocs/MRU

User Activity

What files accessed?

MEDIUM

Typed URLs

Web Activity

What sites visited?

MEDIUM

UserAssist

Program Execution

What programs run?

LOW

Search Terms

User Intent

What did user search for?


SOC Investigation Workflows

Workflow 1: Malware Persistence Detection (CRITICAL)

Scenario: Suspected malware on endpoint, need to identify persistence mechanisms

Registry Keys to Check (in order):

1. Run Keys (Most Common)

What it tells you: Programs that execute at startup/login

Red Flags:

  • βœ— Unusual executable paths (temp folders, user directories)

  • βœ— Obfuscated filenames (random characters)

  • βœ— PowerShell/cmd.exe with encoded commands

  • βœ— Executables in %TEMP%, %APPDATA%, C:\Users\Public

  • βœ— Misspelt legitimate program names (svchost.exe vs svch0st.exe)


2. Winlogon

What it tells you: Programs executed during Windows login process

Check these values:

  • Shell - Should be "Explorer.exe" ONLY

  • Userinit - Should be "C:\Windows\system32\userinit.exe,"

  • TaskMan - Should not exist (if exists, investigate)

Red Flags:

  • βœ— Additional executables appended to Shell value

  • βœ— Modified Userinit path or additional programs

  • βœ— TaskMan value pointing to malware (hijacks Task Manager)


3. Services

What it tells you: Windows services (common persistence for advanced malware)

PowerShell - Filter Suspicious Services:

Red Flags:

  • βœ— Service ImagePath in temp/appdata directories

  • βœ— Recently created services (check timestamps)

  • βœ— Services with no DisplayName or Description

  • βœ— ImagePath using cmd.exe or powershell.exe


4. Image File Execution Options (IFEO)

What it tells you: Debugger hijacking - programs executed instead of legitimate ones

Red Flags:

  • βœ— Subkeys for common programs (sethc.exe, taskmgr.exe, etc.)

  • βœ— "Debugger" value pointing to malicious executable

  • βœ— Common targets: sethc.exe (Sticky Keys), utilman.exe (Utility Manager)

Technique: Attacker replaces legitimate program with malware debugger


5. File Extension Hijacking

What it tells you: Malware executes when you run .exe, .bat, .com files

Expected values:

  • exefile: "%1" %*

  • batfile: "%1" %*

  • comfile: "%1" %*

Red Flags:

  • βœ— Additional executable before "%1"

  • βœ— Modified default value (should only be "%1" %*)


6. Command Processor Autorun

What it tells you: Commands executed every time cmd.exe runs

Red Flags:

  • βœ— AutoRun value exists (should not exist by default)

  • βœ— Any PowerShell/cmd commands in AutoRun


7. Browser Helper Objects (BHOs)

What it tells you: Internet Explorer extensions (often malicious)

Red Flags:

  • βœ— Unknown GUIDs (cross-reference with VirusTotal)

  • βœ— Recently added BHOs

  • βœ— BHOs with no associated legitimate software


PowerShell Script: Comprehensive Persistence Check


Workflow 2: User Activity Investigation (High Priority)

Scenario: Insider threat, data theft, or understanding user actions during incident

Recent Files & Programs

1. RecentDocs (Files Opened)

What it tells you: Files recently opened from Windows Explorer

PowerShell - Decode Binary Data:

Forensic Value:

  • Files accessed even if deleted

  • Includes network share files

  • Shows file access order (MRU = Most Recently Used)


2. OpenSaveMRU (Open/Save Dialog Usage)

What it tells you: Files opened/saved via Open/Save dialogs

Subkeys by extension:

  • * - All files

  • txt - Text files

  • pdf - PDF files

  • docx - Word documents

  • etc.

Cross-reference with:

LastVisitedMRU tells you:

  • Which application opened the file

  • Folder path where file was located


3. RunMRU (Start > Run Command History)

What it tells you: Commands executed via Windows Run dialog

Red Flags:

  • βœ— cmd.exe, powershell.exe with suspicious arguments

  • βœ— Execution of files from temp directories

  • βœ— Remote share access (\\server\share)

  • βœ— Use of PsExec, wmic, or other remote tools


4. TypedURLs (Internet Explorer Address Bar)

What it tells you: URLs typed into IE/Windows Explorer address bar

Shows:

  • Manually typed URLs (not bookmarks/links clicked)

  • File paths typed in Windows Explorer

  • Up to 25 most recent entries

Note: Cleared when user clears browsing history


5. UserAssist (Program Execution Tracking)

What it tells you: Programs, shortcuts, control panel applets accessed by user

Important: Values are ROT-13 encoded

PowerShell - Decode UserAssist:

Forensic Value:

  • Execution count for each program

  • Last execution time

  • Shows programs even if deleted


6. Windows Search Terms

What it tells you: What user searched for using Windows Search

Subkeys:

  • 5001 - Internet Search Assistant terms

  • 5603 - Windows files/folders search

  • 5604 - "Word or phrase in a file" search

  • 5647 - "Computers or people" search

Red Flags:

  • βœ— Searches for "password", "confidential", "payroll"

  • βœ— File type searches (.pst, .pdf, financial terms)

  • βœ— User/admin account searches


PowerShell Script: User Activity Timeline


Workflow 3: USB & External Device Investigation

Scenario: Data exfiltration via USB drive, unauthorised device usage

Critical Registry Keys

1. USB Storage Devices

What it tells you: All USB storage devices ever connected

PowerShell - Enumerate USB Devices:


2. Mounted Devices (Drive Letters)

What it tells you: Drive letter assignments for USB and network drives

Shows:

  • \DosDevices\E:, \DosDevices\F:, etc. - USB drive letters

  • Maps drive letters to device serial numbers

Forensic Value:

  • Correlate drive letter to USB device

  • Determine when device was mounted


3. MountPoints2 (User-Specific Device Access)

What it tells you: Which users accessed which devices

Shows:

  • Volume GUIDs for accessed devices

  • Network share paths (\server\share)

Cross-reference: Match GUIDs in MountPoints2 to MountedDevices to identify USB devices per user


4. Network Drive Mapping

What it tells you: Recently mapped network drives

Red Flags:

  • βœ— Connections to unknown file servers

  • βœ— Administrative shares (C$, ADMIN$, IPC$)

  • βœ— Temporary network shares


PowerShell Script: USB & Device Investigation


Workflow 4: Network & Lateral Movement Investigation

Scenario: Detect lateral movement, remote access, credential dumping

Critical Indicators

1. Network Share Access (MountPoints2)

What it tells you: Remote shares accessed by user

Look for:

  • ##servername#sharename - Network share format

  • Administrative shares: ##server#C$, ##server#ADMIN$

  • Unusual share names: ##server#Temp$, ##server#Exfil$

Red Flags:

  • βœ— Access to multiple servers (horizontal movement)

  • βœ— Administrative shares (C$, ADMIN$)

  • βœ— Non-standard share names

  • βœ— Access from non-admin accounts


2. Remote Desktop Activity

What it tells you: RDP configuration and potential remote access

Check:

  • fDenyTSConnections = 0 means RDP is ENABLED

  • PortNumber = RDP port (default 3389)

PowerShell - Check RDP Status:


3. Startup Approved Run (Network Locations)

What it tells you: Programs configured to run from network shares

Red Flags:

  • βœ— Executables running from UNC paths

  • βœ— Scripts from network shares at startup


PowerShell Script: Network Activity Investigation


Workflow 5: System Information (Quick Triage)

Scenario: Need system context during incident response

Essential System Info


PowerShell Script: System Information Quick Triage


Advanced: Protected Storage & Credentials

Windows Protected Storage

What it tells you: Stored passwords (IE AutoComplete, Outlook, etc.)

Location:

Note: Hidden by Registry Editor, even from administrators

Access Methods:

  • Use specialised tools (NirSoft Protected Storage PassView)

  • Requires appropriate privileges

  • Data is encrypted per user account


LSA Secrets & Autologon Passwords

What it tells you: Cached credentials, service account passwords

Red Flags:

  • βœ— AutoAdminLogon = 1 (auto login enabled)

  • βœ— DefaultPassword value exists (plain text password!)

  • βœ— LSA Secrets accessible (credential dumping indicator)


SOC Incident Response Cheatsheet

Quick Commands for Live Response

Rapid Persistence Check


USB Device Quick Check


User Activity Quick Check


PowerShell One-Liners


Detection Rules & IOCs

High-Confidence Malware Indicators

Run Key Patterns:

Service Patterns:

File Extension Hijacking:

IFEO Abuse:


Common Anti-Forensics Techniques

1. Clearing MRU Lists

Action: User runs "Clear Recent Items" or third-party cleaners

What's deleted:

  • RecentDocs

  • RunMRU

  • TypedURLs

  • OpenSaveMRU

  • LastVisitedMRU

Detection:

  • Check for presence of CCleaner, BleachBit in installed programs

  • Look for execution evidence in Prefetch/Amcache

  • MRU keys missing = potential evidence destruction


2. Registry Key Deletion

Action: Attacker deletes persistence keys after establishing alternate persistence

Detection:

  • Registry transaction logs may contain deleted keys

  • Volume Shadow Copies preserve old registry state

  • Use RegRipper with VSS to compare historical state


3. Timestamp Manipulation

Action: Modify registry key LastWriteTime

Detection:

  • Difficult to detect without baseline

  • Compare with other timestamp sources (event logs, file system)

  • Unusual timestamp patterns (all keys same time)


Registry Analysis Tools

Built-in Windows

  • reg.exe - Command-line registry editor

  • regedit.exe - GUI registry editor

  • PowerShell - Registry PSDrive (HKLM:, HKCU:)

Forensic Tools

  • RegRipper - Automated registry parsing (best for offline analysis)

  • Registry Explorer (Eric Zimmerman) - GUI registry viewer with bookmarks

  • RECmd - Command-line registry parser

  • Registry Viewer (AccessData) - Commercial option

Live Response Tools

  • KAPE - Collection of registry hives and triage

  • Velociraptor - Remote registry collection and analysis

  • GRR - Google Rapid Response for enterprise scale


Exporting Registry for Analysis

Export Specific Keys

User Registry Hives

PowerShell - Mass Export


Registry Forensics Best Practices

Live System Analysis

βœ… Do:

  • Use non-invasive read-only commands

  • Export keys before making changes

  • Document all actions with timestamps

  • Use PowerShell for scripting (logged in transcripts)

❌ Don't:

  • Modify registry during investigation

  • Run untrusted scripts as admin

  • Clear or delete keys during live analysis

  • Shutdown without checking ClearPagefileAtShutdown


Offline Analysis

βœ… Do:

  • Copy entire registry hives for analysis

  • Mount hives read-only

  • Use RegRipper for automated extraction

  • Check Volume Shadow Copies for historical state

  • Document hive file hashes before analysis

❌ Don't:

  • Analyse on production system

  • Mount hives in write mode

  • Forget to check transaction logs (.LOG, .LOG1, .LOG2)


Documentation

βœ… Document:

  • All commands executed

  • Timestamp of analysis

  • Registry key paths and values found

  • Suspicious entries with context

  • Tool versions used

  • Hash values of exported hives


Quick Reference: Registry Hive Locations

System Hives (HKLM)

User Hives

Transaction Logs


Investigation Checklist

Malware/Persistence Investigation

  • [ ] Check all Run/RunOnce keys (HKLM and HKCU)

  • [ ] Check Winlogon Shell and Userinit values

  • [ ] Enumerate all services for suspicious ImagePath

  • [ ] Check IFEO for debugger hijacking

  • [ ] Verify file extension associations (exefile, batfile, comfile)

  • [ ] Check Command Processor AutoRun

  • [ ] Review Browser Helper Objects

  • [ ] Check Active Setup entries

  • [ ] Review Startup Approved items

User Activity Investigation

  • [ ] Enumerate RecentDocs

  • [ ] Check OpenSaveMRU and LastVisitedMRU

  • [ ] Review RunMRU command history

  • [ ] Extract TypedURLs

  • [ ] Decode UserAssist entries

  • [ ] Check Windows Search terms (ACMru)

  • [ ] Review TypedPaths (manually entered paths)

Data Exfiltration Investigation

  • [ ] Enumerate USB devices (USBSTOR)

  • [ ] Check MountedDevices for drive letters

  • [ ] Review MountPoints2 for user device access

  • [ ] Check mapped network drives

  • [ ] Look for network share connections

  • [ ] Review external device timeline

Lateral Movement Investigation

  • [ ] Check MountPoints2 for remote shares

  • [ ] Review network drive mappings

  • [ ] Check RDP status and configuration

  • [ ] Look for PsExec indicators

  • [ ] Review authentication methods (Winlogon)

  • [ ] Check for credential dumping tools


Common SOC Use Cases

Use Case 1: Ransomware Detection

Indicators to check:

  • New Run keys pointing to suspicious executables

  • Services with odd names or temp paths

  • Command Processor AutoRun

  • Recent file activity (RecentDocs) showing mass file access

  • UserAssist showing ransomware executable launch


Use Case 2: Insider Threat

Indicators to check:

  • USB device connections (USBSTOR)

  • Files accessed via OpenSaveMRU

  • Network share mappings to external/personal storage

  • Search terms indicating data theft intent

  • Typed URLs to file-sharing sites


Use Case 3: Credential Theft

Indicators to check:

  • ProcDump execution (memory dump tool)

  • Access to Protected Storage

  • Winlogon AutoAdminLogon enabled

  • LSA Secrets access attempts

  • Mimikatz or similar tool indicators


Use Case 4: Lateral Movement

Indicators to check:

  • Multiple remote share connections (MountPoints2)

  • Administrative share usage (C$, ADMIN$)

  • RDP enabled on workstation

  • PSExec or remote execution tools

  • Network drive mappings to multiple hosts


Summary: Critical Registry Keys by Investigation Type

Investigation Type
Critical Keys

Malware Persistence

Run, RunOnce, Services, Winlogon, IFEO

User Activity

RecentDocs, OpenSaveMRU, RunMRU, TypedURLs

USB/Data Exfil

USBSTOR, MountedDevices, MountPoints2

Lateral Movement

MountPoints2 (shares), Map Network Drive MRU

Credential Theft

Winlogon (autologon), Protected Storage

System Info

CurrentVersion, ComputerName, TimeZone

Key Principle: Registry analysis reveals attacker actions even after files are deleted - persistence mechanisms, user activity, and device usage leave persistent traces that survive file deletion and anti-forensics efforts.

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