Difference between pages "Google Chrome" and "Executable"

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Google Chrome is a [[Web Browser|web browser]] developed by Google Inc.
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{{expand}}
  
== Configuration ==
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An executable file is used to perform tasks according to encoded instructions. Executable files are sometimes also referred to as binaries which technically can be considered a sub class of executable files.
The Google Chrome configuration can be found in the '''Preferences''' file.
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On Linux
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There are multiple families of executable files:
<pre>
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* Scripts; e.g. shell scripts, batch scripts (.bat)
/home/$USER/.config/google-chrome/Default/Preferences
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* DOS, Windows executable files (.exe) which can be of various formats like: MZ, PE/COFF, NE
</pre>
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* ELF
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* Mach-O
  
On MacOS-X
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== External Links ==
<pre>
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* [http://en.wikipedia.org/wiki/Executable Wikipedia: Executable]
/Users/$USER/Library/Application Support/Google/Chrome/Default/Preferences
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* [ftp://ftp.cs.wisc.edu/paradyn/papers/Rosenblum10prov.pdf Extracting Compiler Provenance from Program Binaries], by Nathan E. Rosenblum, Barton P. Miller, Xiaojin Zhu, June 2010
</pre>
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On Windows XP
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=== ELF ===
<pre>
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* [http://robinhoksbergen.com/papers/howto_elf.html Manually Creating an ELF Executable], by Robin Hoksbergen
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Google\Chrome\User Data\Default\Preferences
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</pre>
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On Windows Vista and later
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=== MZ, PE/COFF ===
<pre>
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* [http://en.wikipedia.org/wiki/Portable_Executable Wikipedia: Portable Executable]
C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Preferences
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* [http://msdn.microsoft.com/en-us/windows/hardware/gg463119.aspx Microsoft PE and COFF Specification]
</pre>
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* [http://msdn.microsoft.com/en-us/magazine/ms809762.aspx Peering Inside the PE: A Tour of the Win32 Portable Executable File Format], by Matt Pietrek, March 1994
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* [http://www.microsoft.com/msj/0797/hood0797.aspx Under the Hood], by Matt Pietrek, July 1997
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* [http://msdn.microsoft.com/en-us/magazine/cc301805.aspx An In-Depth Look into the Win32 Portable Executable File Format], by Matt Pietrek, February 2002
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* [https://googledrive.com/host/0B3fBvzttpiiSd1dKQVU0WGVESlU/Executable%20(EXE)%20file%20format.pdf MZ, PE-COFF executable file format (EXE)], by the [[libexe|libexe project]], October 2011
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* [http://seclists.org/fulldisclosure/2013/Oct/157 The Internal of Reloc .text], Full Disclosure Mailing list, October 21, 2013
  
Or for '''Chromium'''
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=== DBG, PDB ===
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* [http://en.wikipedia.org/wiki/Program_database Wikipedia: Program database]
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* [http://www.debuginfo.com/articles/debuginfomatch.html Matching Debug Information], by debuginfo.com
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* [http://support.microsoft.com/kb/121366 Description of the .PDB files and of the .DBG files], by [[Microsoft]]
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* [http://msdn.microsoft.com/en-us/library/ff553493(v=vs.85).aspx Public and Private Symbols], by [[Microsoft]]
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* [http://msdn.microsoft.com/en-us/library/windows/desktop/ms679293(v=vs.85).aspx DbgHelp Structures], by [[Microsoft]]
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* [http://web.archive.org/web/20070915060650/http://www.x86.org/ftp/manuals/tools/sym.pdf Internet Archive: Microsoft Symbol and Type Information], by [[Microsoft]]
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* [http://pierrelib.pagesperso-orange.fr/exec_formats/MS_Symbol_Type_v1.0.pdf Microsoft Symbol and Type Information]
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* [https://code.google.com/p/pdbparse/wiki/StreamDescriptions Stream Descriptions], [https://code.google.com/p/pdbparse/ pdbparse project]
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* [http://sourceforge.net/p/mingw-w64/code/HEAD/tree/experimental/tools/libmsdebug/ libmsdebug], by the [[MinGW|MinGW project]]
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* [http://moyix.blogspot.com/2007/10/types-stream.html The Types Stream], by [[Brendan Dolan-Gavitt]], October 4, 2007
  
On Linux
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=== Minidump ===
<pre>
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* [http://msdn.microsoft.com/en-us/library/windows/desktop/ms680378(v=vs.85).aspx MSDN: MINIDUMP_HEADER structure]
/home/$USER/.config/chromium/Default/Preferences
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* [https://code.google.com/p/google-breakpad/source/browse/trunk/src/google_breakpad/common/minidump_format.h minidump_format.h], by [[Google]], 2006
</pre>
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* [http://moyix.blogspot.com/2008/05/parsing-windows-minidumps.html Parsing Windows Minidumps], by [[Brendan Dolan-Gavitt]], May 7, 2008
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* [http://web.archive.org/web/20110814041817/http://www.stackhash.com/blog/post/Format-of-a-minidump-(mdmp)-file.aspx Format of a minidump (mdmp) file], Internet Archive: StackHash blog, May 16, 2011
  
On MacOS-X
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=== Mach-O ===
<pre>
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* [http://en.wikipedia.org/wiki/Mach-O Wikipedia: Mach-O]
/Users/$USER/Library/Application Support/Chromium/Default/Preferences
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</pre>
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On Windows XP
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=== Packers ===
<pre>
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* [http://www.woodmann.com/crackz/Packers.htm Packers & Unpackers]
C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Chromium\User Data\Default\Preferences
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</pre>
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On Windows Vista and later
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== Tools ==
<pre>
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C:\Users\%USERNAME%\AppData\Local\Chromium\User Data\Default\Preferences
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</pre>
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=== Plugins ===
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=== MZ, PE/COFF ===
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* [https://code.google.com/p/pefile/ pefile], multi-platform Python module to read and work with Portable Executable (aka PE) files
  
Information about plugins can be found under the "plugins section" of the Preferences file.
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=== PDB ===
 
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* [https://code.google.com/p/pdbparse/ pdbparse], Open-source parser for Microsoft debug symbols (PDB files)
=== DNS Prefetching ===
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DNS is prefetched for related sites, e.g. links on the page.
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This behavior is controlled by the setting "Predict network actions to improve page load performance", which is enabled by default.
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If enabled the Preferences file contains:
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<pre>
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  "dns_prefetching": {
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      "enabled": true,
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</pre>
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If disabled the Preferences file contains:
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<pre>
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  "dns_prefetching": {
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      "enabled": false,
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</pre>
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== Start-up DNS queries ==
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When Chrome starts it queries for several non-existing hostnames that consists of a 10 random characters, E.g.
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<pre>
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ttrgoiknff.mydomain.com
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bxjhgftsyu.mydomain.com
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yokjbjiagd.mydomain.com
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</pre>
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This is used to determine if your ISP is hijacking NXDOMAIN results [http://www.google.com/support/forum/p/Chrome/thread?tid=3511015c72a7b314&hl=en].
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== Disk Cache ==
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The Google Chrome disk cache can be found in:
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On Linux
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<pre>
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/home/$USER/.config/google-chrome/Default/Application Cache/Cache/
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</pre>
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On MacOS-X
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<pre>
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/Users/$USER/Caches/Google/Chrome/Default/Cache/
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</pre>
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On Windows XP
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<pre>
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C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Google\Chrome\User Data\Cache\
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</pre>
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On Windows Vista and later
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<pre>
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C:\Users\%USERNAME%\AppData\Local\Google\Chrome\User Data\Default\Cache\
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</pre>
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The Chrome Cache contains different files with the following file names:
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* index
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* data_#; where # contains a decimal digit.
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* f_######; where # contains a hexadecimal digit.
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For more info see Chrome developers site [http://www.chromium.org/developers/design-documents/network-stack/disk-cache].
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== History ==
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Chrome stores the history of visited sites in a file named '''History'''. This file uses the [[SQLite database format]].
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The '''History''' file can be found in same location as the '''Preferences''' file.
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There is also '''Archived History''' that predates information in the '''History''' file.
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Note that the '''Archived History''' only contains visits.
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=== Timestamps ===
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The '''History''' file uses the different timestamps.
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==== visits.visit_time ====
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The '''visits.visit_time''' is in (the number of) microseconds since January 1, 1601 UTC
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Some Python code to do the conversion into human readable format:
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<pre>
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date_string = datetime.datetime( 1601, 1, 1 )
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            + datetime.timedelta( microseconds=timestamp )
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</pre>
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Note that this timestamp is not the same as a Windows filetime which is (the number of) 100 nanoseconds since January 1, 1601 UTC
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==== downloads.start_time ====
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The '''downloads.start_time''' is in (the number of) seconds since January 1, 1970 UTC
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Some Python code to do the conversion into human readable format:
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<pre>
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date_string = datetime.datetime( 1970, 1, 1 )
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            + datetime.timedelta( seconds=timestamp )
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</pre>
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=== Example queries ===
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Some example queries:
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To get an overview of the visited sites:
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<pre>
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SELECT datetime(((visits.visit_time/1000000)-11644473600), "unixepoch"), urls.url, urls.title FROM urls, visits WHERE urls.id = visits.url;
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</pre>
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Note that the visit_time conversion looses precision.
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To get an overview of the downloaded files:
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<pre>
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SELECT datetime(downloads.start_time, "unixepoch"), downloads.url, downloads.full_path, downloads.received_bytes, downloads.total_bytes FROM downloads;
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</pre>
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How the information of the downloaded files is stored in the database can vary per version of Chrome as of version 26:
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<pre>
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SELECT datetime(((downloads.start_time/1000000)-11644473600), "unixepoch"), downloads.target_path, downloads_url_chains.url, downloads.received_bytes, downloads.total_bytes \
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FROM downloads, downloads_url_chains WHERE downloads.id = downloads_url_chains.id;
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</pre>
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== See Also ==
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* [[SQLite database format]]
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== External Links ==
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* [http://en.wikipedia.org/wiki/Google_Chrome Wikipedia article on Google Chrome]
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* [http://www.chromium.org/user-experience/user-data-directory The Chromium Projects - User Data Directory]
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* [http://www.chromium.org/developers/design-documents/network-stack/disk-cache Chrome Disk Cache]
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* [http://www.google.com/support/forum/p/Chrome/thread?tid=3511015c72a7b314&hl=en Chrome support forum article random 10 character hostnames on startup]
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* [http://www.useragentstring.com/pages/Chrome/ Chrome User Agent strings]
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* [http://computer-forensics.sans.org/blog/2010/01/21/google-chrome-forensics/ Google Chrome Forensics] by [[Kristinn Guðjónsson]], January 21, 2010
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* [http://linuxsleuthing.blogspot.ch/2013/02/cashing-in-on-google-chrome-cache.html?m=1 Cashing in on the Google Chrome Cache], [[John Lehr]], February 24, 2013
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* [http://www.obsidianforensics.com/blog/history-index-files-removed-from-chrome/ History Index files removed from Chrome v30], by Ryan Benson, October 2, 2013
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* [https://hindsight-internet-history.googlecode.com/files/Evolution_of_Chrome_Databases.png Evolution of Chrome Databases], by Ryan Benson, October 2, 2013
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== Tools ==
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=== Open Source ===
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* [https://code.google.com/p/hindsight-internet-history/ hindsight-internet-history]
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[[Category:Applications]]
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=== Minidump ===
[[Category:Web Browsers]]
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* [http://support.microsoft.com/kb/315271 Dumpchk.exe], by [[Microsoft]]
 +
* [http://amnesia.gtisc.gatech.edu/~moyix/minidump.py minidump.py], by [[Brendan Dolan-Gavitt]]

Revision as of 13:11, 18 May 2014

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Please help to improve this article by expanding it.
Further information might be found on the discussion page.

An executable file is used to perform tasks according to encoded instructions. Executable files are sometimes also referred to as binaries which technically can be considered a sub class of executable files.

There are multiple families of executable files:

  • Scripts; e.g. shell scripts, batch scripts (.bat)
  • DOS, Windows executable files (.exe) which can be of various formats like: MZ, PE/COFF, NE
  • ELF
  • Mach-O

External Links

ELF

MZ, PE/COFF

DBG, PDB

Minidump

Mach-O

Packers

Tools

MZ, PE/COFF

  • pefile, multi-platform Python module to read and work with Portable Executable (aka PE) files

PDB

  • pdbparse, Open-source parser for Microsoft debug symbols (PDB files)

Minidump