Difference between revisions of "Vista thumbcache"

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== Thumbnail Creation Process ==
 
== Thumbnail Creation Process ==
  
[[Windows]] Vista creates thumbnails for files on:
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[[Windows]] Vista creates thumbnails for files on different media, including:
  
* [[Hard Drive | Hard drives]]
 
 
* Removable devices
 
* Removable devices
 
* Network drives
 
* Network drives
 
* Encrypted containers (e.g. [[PGP]] Desktop, [[TrueCrypt]], [[BestCrypt]])
 
* Encrypted containers (e.g. [[PGP]] Desktop, [[TrueCrypt]], [[BestCrypt]])
  
[[Windows]] Vista doesn't create thumbnails for files encrypted using [[EFS]] unless thumbcache directory is encrypted too.
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[[Windows]] Vista doesn't create thumbnails for files encrypted using [[EFS]] unless thumbcache directory is encrypted too; [[Windows]] Vista doesn't delete thumbnails for files after they were encrypted using [[EFS]].
 +
 
 +
Some programs may generate thumbnails for some file types which are displayed in Windows Explorer, but not stored in the thumbcache (e.g. Ascon Kompas).
  
 
== Linking thumbnails with original files ==
 
== Linking thumbnails with original files ==
  
 +
=== Using Windows Indexer ===
 +
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==== Windows Powershell ====
  
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==== HEX editor ====
  
 
== External Links ==
 
== External Links ==
  
 
* [http://www.whereisyourdata.co.uk/data/modules/wfdownloads/visit.php?cid=4&lid=9 Forensic Implications of Windows Vista, Barrie Stewart, 2007]
 
* [http://www.whereisyourdata.co.uk/data/modules/wfdownloads/visit.php?cid=4&lid=9 Forensic Implications of Windows Vista, Barrie Stewart, 2007]

Revision as of 09:30, 19 March 2009

Contents

Overview

Windows Vista stores thumbnails in the following directory: \Users\\AppData\Local\Microsoft\Windows\Explorer

This directory contains following files:

  • thumbcache_idx.db
  • thumbcache_32.db, thumbcache_96.db, thumbcache_256.db, and thumbcache_1024.db
  • thumbcache_sr.db

Thumbnails are stored in thumbcache_NN.db files in different formats (e.g. BMP) and can be extracted using file carving. There are several tools that can work with Vista Thumbcache: dmThumbs, Thumbs.db Viewer, and FTK. Unfortunately, there is no information in the thumbcache that can easily link thumbnails with original files in all cases. One of the ways to link thumbnails with original files is to use Windows Indexer (Windows.edb) database.

Thumbcache Format

Thumbcache format is described here.

In general, every thumbnail in cache is associated with two 64-bit variables. First variable (sometimes called Unique ID, Secret, File ID) associates data in file thumbcache_idx.db with thumbnail data in thumbcache_NN.db files; the purpose of this variable is unclear. Another variable is Thumbnail Cache ID (sometimes called Thumbnail filename (in FTK), File Ref) is used to link thumbnails with original files. Actually, Thumbnail Cache ID is represented as Unicode string of HEX encoding.

Thumbnail Creation Process

Windows Vista creates thumbnails for files on different media, including:

Windows Vista doesn't create thumbnails for files encrypted using EFS unless thumbcache directory is encrypted too; Windows Vista doesn't delete thumbnails for files after they were encrypted using EFS.

Some programs may generate thumbnails for some file types which are displayed in Windows Explorer, but not stored in the thumbcache (e.g. Ascon Kompas).

Linking thumbnails with original files

Using Windows Indexer

Windows Powershell

HEX editor

External Links