File and Folder Access Investigation Guide
Complete DFIR Workflow & Cheatsheet
π Table of Contents
π― Artifact Priority Matrix
Quick Decision Guide: What to Check First?
Recent Document Access
RecentDocs, LNK Files
OpenSaveMRU, Office MRU
5-15 min
Deleted Files
Recycle Bin ($I/$R), Thumbcache
Windows Search, IE History
15-30 min
User File Focus
Recent Folder, Jump Lists
LastVisitedMRU
10-20 min
Office Document Activity
Office File MRU, Trust Records
Reading Locations, OAlerts
15-30 min
Data Exfiltration
RecentDocs, LNK Files
OpenSaveMRU, LastVisitedMRU
30-45 min
Insider Threat
Office MRU, Recent Files
Trust Records, Search Terms
30-60 min
Malicious Documents
Office Trust Records
Office MRU, LNK Files
15-30 min
User Search Behavior
WordWheelQuery, TypedPaths
Recent Files
10-15 min
Network Share Access
LNK Files, IE History
LastVisitedMRU
20-30 min
π Investigation Framework
Phase 1: Quick Triage (First 15 Minutes)
Determine Investigation Scope:
Quick Wins - Check These Immediately:
Phase 2: Artifact Collection (Live System)
Critical Files to Collect:
π MRU Artifacts Analysis
1. OpenSaveMRU
Overview:
Purpose: Track files opened/saved via Windows Open/Save dialogs
Location: NTUSER.DAT
Coverage: Office apps, browsers, chat clients, most GUI applications
Retention: Last 20 files per extension
Registry Locations:
Structure:
Key Features:
Each extension tracks last 20 files
*key = most recent files regardless of extensionMRUListEx= ordered list (most recent first)Stores full path (as PIDL + filename)
Collection & Analysis:
Using Registry Explorer:
Manual Registry Query:
Using RegRipper:
PowerShell Parsing:
Investigation Tips:
1. Recent File Access by Type:
2. Timeline Construction:
3. Red Flags:
2. LastVisitedMRU
Overview:
Purpose: Track applications and last folder they accessed
Forensic Value: Shows which app accessed which folder
Location: NTUSER.DAT
Registry Location:
Key Information:
Application executable name
Last folder path accessed by that application
Order of access (MRUListEx)
Collection & Analysis:
Using RegRipper:
Investigation Tips:
What to Look For:
Cross-Reference Strategy:
π Recent Files Analysis
1. RecentDocs Registry Key
Overview:
Purpose: Track last 150 files/folders opened
Location: NTUSER.DAT per user
Organisation: By file extension + rollup key
Forensic Gold: Survives file deletion!
Registry Location:
Structure:
Key Features:
Root Key
All file types
Last 150
Key LastWriteTime = most recent
Folder Subkey
Folders only
Last 30
Key LastWriteTime
Extension Subkeys
Per file type
Last 20 each
Key LastWriteTime
MRUListEx
Access order
N/A
Ordered list
Collection & Analysis:
Manual Registry Query:
Using Registry Explorer:
Using RegRipper:
PowerShell Parsing:
Investigation Workflows:
1. Recent File Timeline:
2. Deleted File Detection:
3. Sensitive Document Access:
4. External Drive Usage:
Red Flags:
2. Recent Folder (LNK Files Location)
Overview:
Physical Location:
C:\Users\{Username}\AppData\Roaming\Microsoft\Windows\RecentContains: LNK shortcut files for recently accessed files
Forensic Value: Rich metadata + survives file deletion
What's Stored:
LNK files (Windows shortcuts)
Automatically created on file access
Persists after target file deletion
Contains target file metadata
Note: See detailed LNK Files section below for analysis
π LNK Files Analysis
Overview
What are LNK Files?
Windows shortcut files
Automatically created when user opens file
Rich forensic metadata
Persist after target deletion
Locations:
Key Forensic Information:
LNK Creation Time
First time file of that name opened
LNK file metadata
LNK Modified Time
Last time file of that name opened
LNK file metadata
Target Created Time
When target file was created
Embedded in LNK
Target Modified Time
When target was last modified
Embedded in LNK
Target Accessed Time
When target was last accessed
Embedded in LNK
Target Path
Original location of file
Embedded in LNK
Target Size
Size of target file
Embedded in LNK
Volume Info
Drive name, type, serial number
Embedded in LNK
Network Share
UNC path if on network
Embedded in LNK
Machine ID
NetBIOS name of system
Embedded in LNK
Important Behaviors
1. LNK Overwriting (Pre-Windows 10):
2. LNK with Extension (Windows 10+):
3. LNK Persistence:
Collection & Analysis
Collection:
Quick Analysis (Command Line):
Using ExifTool:
Using LECmd (Link Explorer Command Line):
LECmd Output Analysis:
Investigation Workflows
1. File Access Timeline:
2. Deleted File Recovery:
3. Network Share Access (Lateral Movement):
4. USB Drive Tracking:
5. Cross-Machine Activity:
Red Flags
Pro Tips
β Timeline Reconstruction: Combine LNK timestamps with file timestamps for complete picture
β USB Device Tracking: Volume serial number uniquely identifies USB device
β Network Mapping: LNK files show lateral movement paths
β Deleted Evidence: LNK survives deletion - crucial for proving file existed
β οΈ Filename Limitation: Pre-Win10 systems overwrite LNK for same filename
β οΈ Hidden Extensions: .lnk extension never shown in Windows Explorer
π Office Artifacts Analysis
1. Office File MRU
Overview:
Purpose: Track recent files per Office application
Advantage over RecentDocs: Includes full path + last opened time
Location: NTUSER.DAT per user
Office Versions:
16.0 = Office 2016/2019/Microsoft 365
15.0 = Office 2013
14.0 = Office 2010
Registry Locations:
Standard Office:
Microsoft 365 (Personal Account):
Microsoft 365 (Azure AD):
Collection & Analysis:
Manual Query:
Using Registry Explorer:
PowerShell Parsing:
Investigation Workflows:
1. Recent Document Activity:
2. Sensitive Document Access:
3. Network Share Document Access:
4. External Drive Documents:
5. Deleted Document Evidence:
2. MS Word Reading Locations
Overview:
Feature: Word 2013+ tracks user's position in document
Forensic Value: Proves document was opened + how long user spent in it
Location: NTUSER.DAT
Registry Location:
Key Information:
Document path
Last cursor position in document
Last closed time
Duration of reading session (with File MRU data)
Collection & Analysis:
Using Registry Explorer:
Investigation Use:
3. Office Trust Records
Overview:
Purpose: Track documents where user enabled macros/editing
Security Significance: Macro-enabled documents = common malware vector
Location: NTUSER.DAT per Office app
Registry Locations:
Key Information:
Document path (local or network)
Time document was trusted
Permissions granted (macros enabled, editing enabled)
Critical: Value ending in
FF FF FF 7F= Macros enabled!
Collection & Analysis:
Manual Query:
PowerShell - Find Macro-Enabled Documents:
Investigation Workflows:
1. Malicious Document Detection:
2. Timeline Correlation:
3. Document Source Analysis:
Red Flags:
Malware Investigation:
4. Office OAlerts
Overview:
Purpose: Log Office application alerts/prompts
Location: OAlerts.evtx
Event ID: 300 (all Office apps)
Forensic Value: User interactions with Office
Location:
Key Information:
Office application name
Alert dialog message
User response
Timestamp
Collection:
Analysis:
Using EvtxECmd:
PowerShell Query:
Investigation Use:
ποΈ Deleted Items Investigation
1. Recycle Bin Analysis
Overview:
Windows 7+: Uses $I and $R files per deleted item
Location: C:$Recycle.Bin{User-SID}\
Forensic Value: Deleted file recovery + deletion timeline
Structure:
File Types:
$I files: Metadata (original filename, path, deletion time, size)
$R files: Actual deleted file content (recoverable)
6-character identifier: Links $I and $R files together
Key Information:
Original Filename
Full original name
$I file
Original Path
Complete path before deletion
$I file
File Size
Size of deleted file
$I file
Deletion Time
When file was deleted
$I file
File Content
Actual file data
$R file
Collection & Analysis:
Collection:
Using RBCmd (Recycle Bin Command Line):
PowerShell Parsing:
Investigation Workflows:
1. Deleted File Timeline:
2. Sensitive File Deletion:
3. Mass Deletion Detection:
4. File Recovery:
Red Flags:
Pro Tips:
β Recovery Possible: $R files are intact until overwritten
β Timeline Evidence: Deletion time preserved in $I files
β User Attribution: SID folder identifies who deleted files
β οΈ Bypass: Files deleted via command line with /F switch bypass Recycle Bin
β οΈ Size Limit: Very large files may bypass Recycle Bin
2. Thumbcache Analysis
Overview:
Purpose: Store thumbnail images of pictures, videos, documents
Location: Per-user Explorer folder
Forensic Value: Thumbnails survive file deletion!
Available: Windows Vista+
Location:
Files:
Key Information:
Thumbnail image (visual)
Thumbnail Cache ID
File hash
Image can be extracted even if original deleted
Collection:
Analysis:
Using thumbcache_viewer.exe:
Using thumbs_viewer.exe:
Investigation Workflows:
1. Deleted Image Recovery:
2. Content Verification:
3. Timeline Construction:
Cross-Reference Strategy:
3. Windows Search Database
Overview:
Purpose: Index files for fast searching
Format: ESE database (Extensible Storage Engine)
Location: System-wide (not per-user)
Forensic Value: File metadata + partial content + survives deletion
Location:
Key Information:
File paths
File metadata (size, dates, properties)
Partial file content (indexed text)
Email metadata
Document properties
Over 900 file types indexed
Collection:
Analysis:
Using ESEDatabaseView (NirSoft):
Using KAPE:
Investigation Workflows:
1. Deleted File Search:
2. Keyword Search:
3. Email Investigation:
4. Thumbs.db (Legacy - Windows XP)
Overview:
Purpose: Store thumbnails per folder
Available: Windows XP (can appear on modern systems via UNC)
Location: Each folder with images
Forensic Value: Thumbnails + filenames (XP only)
Key Information (XP):
Thumbnail image
Original filename
Last modification time
Modern Systems:
Thumbs.db may be created when viewing folders via UNC paths
Limited metadata compared to XP
Collection:
5. Internet Explorer File Access History
Overview:
Purpose: IE history contains local file access via file:/// protocol
Forensic Value: Tracks file opening even if not opened in browser
Location: WebCache database
Persists: Even on Windows 11 without IE!
Location:
Key Information:
Local file paths
Access times
File:/// protocol entries
Network share (UNC) access
Format:
Collection:
Analysis:
Using Nirsoft BrowsingHistoryView:
Using ESEDatabaseView:
Investigation Use:
π Search and Navigation History
1. WordWheelQuery
Overview:
Purpose: Store Windows Search keywords from File Explorer
Location: NTUSER.DAT per user
Forensic Value: Shows what user searched for
Registry Location:
Key Information:
Search keywords (Unicode)
Temporal order (MRUListEx)
Last search (registry LastWriteTime)
Collection & Analysis:
Using Registry Explorer:
Using RegRipper:
Investigation Workflows:
1. Keyword Analysis:
2. Incident Investigation:
Red Flags:
2. TypedPaths
Overview:
Purpose: Track paths typed directly into File Explorer address bar
Location: NTUSER.DAT
Forensic Value: Shows user knowledge of specific locations
Registry Location:
Key Information:
Paths manually typed by user
Order of entry (url1, url2, etc.)
Indicates intentional navigation
Collection & Analysis:
Using Registry Explorer:
Investigation Workflows:
1. Hidden Location Detection:
2. Intentional Access:
Red Flags:
π Investigation Playbooks
Playbook 1: Data Exfiltration Investigation
Objective: Detect and quantify data theft
Phase 1: Document Access (30 min)
Phase 2: External Media (30 min)
Phase 3: Network Shares (30 min)
Phase 4: Timeline Construction (45 min)
Phase 5: Quantification (30 min)
Playbook 2: Malicious Document Investigation
Objective: Investigate macro-enabled document compromise
Phase 1: Trust Record Analysis (15 min)
Phase 2: Document Source (20 min)
Phase 3: Execution Timeline (30 min)
Phase 4: Impact Assessment (45 min)
Phase 5: IOC Extraction (30 min)
Playbook 3: Insider Threat - Document Access
Objective: Investigate unauthorized document access
Phase 1: Scope Definition (15 min)
Phase 2: Recent Activity (30 min)
Phase 3: Anomaly Detection (45 min)
Phase 4: Search Behaviour (20 min)
Phase 5: Exfiltration Check (45 min)
Playbook 4: Deleted File Recovery
Objective: Recover and analyze deleted files
Phase 1: Recycle Bin (20 min)
Phase 2: Artifact Persistence (30 min)
Phase 3: Visual Evidence (30 min)
Phase 4: File System Analysis (60 min)
Phase 5: Timeline Construction (30 min)
π οΈ Tool Reference
Registry Analysis Tools
Registry Explorer (GUI) - Eric Zimmerman
RegRipper (CLI) - H. Carvey
RECmd (CLI) - Eric Zimmerman
LNK File Analysis Tools
LECmd (CLI) - Eric Zimmerman
ExifTool (CLI)
Recycle Bin Tools
RBCmd (CLI) - Eric Zimmerman
Rifiuti2 (CLI)
Thumbcache Tools
thumbcache_viewer.exe - Thumbsviewer Project
thumbs_viewer.exe - Vinetto Project
Event Log Tools
EvtxECmd (CLI) - Eric Zimmerman
Database Tools
ESEDatabaseView - NirSoft
DB Browser for SQLite
Collection Tools
KAPE - Kroll Artifact Parser and Extractor
FTK Imager
π Quick Reference Cards
Artifact Comparison Matrix
RecentDocs
β Yes
β Survives
β οΈ Key time
β Per user
β No
β UNC paths
OpenSaveMRU
β Yes
β Survives
β οΈ Key time
β Per user
β No
β UNC paths
LastVisitedMRU
β οΈ Folder
β Survives
β οΈ Key time
β Per user
β No
β UNC paths
LNK Files
β Yes
β Survives
β Multiple
β Per user
β Yes
β Full UNC
Office MRU
β Full path
β Survives
β Last open
β Per user
β No
β UNC paths
Trust Records
β Yes
β Survives
β Trust time
β Per user
β No
β UNC paths
Recycle Bin
β Original
β Content!
β Delete time
β SID folder
β Yes
β No
Thumbcache
β οΈ Via ID
β Thumbnails
β No
β Per user
β No
β No
IE History
β file:///
β Survives
β Access
β Per user
β No
β file://
Collection Priority (Live System)
First 5 Minutes:
Next 15 Minutes:
Next 30 Minutes:
Investigation Time Estimates
Quick triage (RecentDocs, searches)
10-15 min
LNK file analysis (50-100 files)
20-30 min
Office artifact analysis
30-45 min
Recycle Bin analysis
15-30 min
Thumbcache extraction
30-60 min
Complete file access timeline
2-3 hours
Data exfiltration investigation
3-4 hours
Insider threat comprehensive analysis
4-6 hours
π Pro Tips
Cross-Referencing Strategy
Timeline Construction
Common Pitfalls
Red Flag Summary
Use this guide for comprehensive file and folder access investigations. Remember: Artifacts persist after deletion - always check multiple sources!
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