homepage
Open menu
Go one level top
  • Train and Certify
    Train and Certify

    Immediately apply the skills and techniques learned in SANS courses, ranges, and summits

    • Overview
    • Courses
      • Overview
      • Full Course List
      • By Focus Areas
        • Cloud Security
        • Cyber Defense
        • Cybersecurity and IT Essentials
        • DFIR
        • Industrial Control Systems
        • Offensive Operations
        • Management, Legal, and Audit
      • By Skill Levels
        • New to Cyber
        • Essentials
        • Advanced
        • Expert
      • Training Formats
        • OnDemand
        • In-Person
        • Live Online
      • Course Demos
    • Training Roadmaps
      • Skills Roadmap
      • Focus Area Job Roles
        • Cyber Defence Job Roles
        • Offensive Operations Job Roles
        • DFIR Job Roles
        • Cloud Job Roles
        • ICS Job Roles
        • Leadership Job Roles
      • NICE Framework
        • Security Provisionals
        • Operate and Maintain
        • Oversee and Govern
        • Protect and Defend
        • Analyze
        • Collect and Operate
        • Investigate
        • Industrial Control Systems
    • GIAC Certifications
    • Training Events & Summits
      • Events Overview
      • Event Locations
        • Asia
        • Australia & New Zealand
        • Latin America
        • Mainland Europe
        • Middle East & Africa
        • Scandinavia
        • United Kingdom & Ireland
        • United States & Canada
      • Summits
    • OnDemand
    • Get Started in Cyber
      • Overview
      • Degree and Certificate Programs
      • Scholarships
    • Cyber Ranges
  • Manage Your Team
    Manage Your Team

    Build a world-class cyber team with our workforce development programs

    • Overview
    • Why Work with SANS
    • Group Purchasing
    • Build Your Team
      • Team Development
      • Assessments
      • Private Training
      • Hire Cyber Professionals
      • By Industry
        • Health Care
        • Industrial Control Systems Security
        • Military
    • Leadership Training
  • Security Awareness
    Security Awareness

    Increase your staff’s cyber awareness, help them change their behaviors, and reduce your organizational risk

    • Overview
    • Products & Services
      • Security Awareness Training
        • EndUser Training
        • Phishing Platform
      • Specialized
        • Developer Training
        • ICS Engineer Training
        • NERC CIP Training
        • IT Administrator
      • Risk Assessments
        • Knowledge Assessment
        • Culture Assessment
        • Behavioral Risk Assessment
    • OUCH! Newsletter
    • Career Development
      • Overview
      • Training & Courses
      • Professional Credential
    • Blog
    • Partners
    • Reports & Case Studies
  • Resources
    Resources

    Enhance your skills with access to thousands of free resources, 150+ instructor-developed tools, and the latest cybersecurity news and analysis

    • Overview
    • Webcasts
    • Free Cybersecurity Events
      • Free Events Overview
      • Summits
      • Solutions Forums
      • Community Nights
    • Content
      • Newsletters
        • NewsBites
        • @RISK
        • OUCH! Newsletter
      • Blog
      • Podcasts
      • Summit Presentations
      • Posters & Cheat Sheets
    • Research
      • White Papers
      • Security Policies
    • Tools
    • Focus Areas
      • Cyber Defense
      • Cloud Security
      • Digital Forensics & Incident Response
      • Industrial Control Systems
      • Cyber Security Leadership
      • Offensive Operations
  • Get Involved
    Get Involved

    Help keep the cyber community one step ahead of threats. Join the SANS community or begin your journey of becoming a SANS Certified Instructor today.

    • Overview
    • Join the Community
    • Work Study
    • Teach for SANS
    • CISO Network
    • Partnerships
    • Sponsorship Opportunities
  • About
    About

    Learn more about how SANS empowers and educates current and future cybersecurity practitioners with knowledge and skills

    • SANS
      • Overview
      • Our Founder
      • Awards
    • Instructors
      • Our Instructors
      • Full Instructor List
    • Mission
      • Our Mission
      • Diversity
      • Scholarships
    • Contact
      • Contact Customer Service
      • Contact Sales
      • Press & Media Enquiries
    • Frequent Asked Questions
    • Customer Reviews
    • Press
    • Careers
  • Contact Sales
  • SANS Sites
    • GIAC Security Certifications
    • Internet Storm Center
    • SANS Technology Institute
    • Security Awareness Training
  • Search
  • Log In
  • Join
    • Account Dashboard
    • Log Out
  1. Home >
  2. Blog >
  3. 'Free Download Manager' Log Extraction
John McCash

'Free Download Manager' Log Extraction

December 17, 2009

Recently I worked on a case that required I reverse engineer some file formats used by the 'Free Download Manager' application. This is a popular download management application available from www.freedownloadmanager.org.

The version of the application I analyzed stores its logs under 'userprofile\Application Data\Free Download Manager'. It uses a number of files to handle different logs and track various in-process tasks. Here's a list of the files I found there:

  • dlmgrsi.sav - This is actually a short executable of some description. Not sure what it's for.
  • downloads.his.sav - Log file using the following format: Starts with the null-terminated header "FDM Downloads History". Then 8 bytes of unknown data, followed by a list of records as follows, terminated by end of file after the last record:
    • 4 byte filename size (little endian)
    • filename
    • 4 byte target path size (little endian)
    • target path
    • 4 byte URL size (little endian)
    • URL
    • 4 bytes of null
    • windows file time #1 (Presumably download start)
    • windows file time #2 (Presumably download end)
    • windows file time #3 (Unknown. All examples found identical to time #2)
    • 8 bytes of file size (little endian)
  • downloads.sav - Much shorter log file, using a different file format.
  • groups.sav - Apppears to be intended for specifying where downloaded files of specified types are to be placed. Starts with the null terminated header "FDM Groups", then 11 bytes of binary data, then records of the form:
    • 4 byte group number
    • 4 byte groupname size (little endian)
    • groupname
    • 4 byte download path size (little endian)
    • download path
    • 4 byte extension list size (little endian)
    • space separated list of extensions
    • 4 nulls
  • history.sav - Yet another, even shorter log file, with a different format.
  • mctasks.sav - My example just had the header "FDM Media Convert Tasks", followed by hex 00 00 00 01 00 00 00 00 00.
  • schedules.sav - My example just had 8 null bytes.
  • sites.sav - My example had nothing but the header "FDM Sites " followed by hex 00 08 38 03 00 00 00 00 00.
  • spider.sav - My example just had the header "FDM Web Pages " followed by hex 00 58 88 06 00 00 00 00 00.
  • uploads.1.sav - My example just had the header "FUM Uploads" followed by hex 00 54 FE 02 00 00 00 00 00.

I spent the majority of my time puzzling out the format of downloads.his.sav, but was able to draw some conclusions about the formats of downloads.sav and history.sav as well. I suspect that these latter two files may be used somewhat more like a database than traditional log files. Either that or the samples I have are corrupted (this is quite possible as they were collected while in use using EnCase Enterprise over the network). Suffice it to say that they have different formats, but also contain target paths, URLs, and windows filetimes. The filetimes can be readily identified for those using EnCase by running Lance Mueller's Windows Timestamp Search EnScript. These files may also be used to track downloads which are still in progress.

I wrote the following short perl script to parse runs of records manually extracted from the downloads.his.sav file or from unallocated space, and output them in CSV format. It doesn't handle the file header and leading binary data, so don't try to feed it the whole file. Note also that it uses the Parse::Win32Registry module from CPAN to convert the Windows filetime values.

use Parse::Win32Registry qw( :REG_
unpack_windows_time
unpack_unicode_string );
while (read(STDIN, $fnsize, 4) == 4) {
$translated_fnsize=unpack(I, $fnsize);
read STDIN, $filename, $translated_fnsize;
print "$filename, ";
read STDIN, $fpsize, 4;
$translated_fpsize=unpack(I, $fpsize);
read STDIN, $filepath, $translated_fpsize;
print "$filepath, ";
read STDIN, $urlsize, 4;
$translated_urlsize=unpack(I, $urlsize);
read STDIN, $url, $translated_urlsize;
print "$url, ";
read STDIN, $nulls, 4;
read STDIN, $firsttime, 8;
$translated_firsttime=unpack(H16, $firsttime);
$time1=unpack_windows_time( $firsttime );
($sec1, $min1, $hour1, $mday1, $mon1, $year1, $wday1, $yday1, $isdst1) = localtime($time1+46800);
$year1+=1900;
$mon1++;
printf "%2.2d/%2.2d/%d, %2.2d:%2.2d:%2.2d, ", $mon1,$mday1,$year1,$hour1,$min1,$sec1;
read STDIN, $secondtime, 8;
$translated_secondtime=unpack(H16, $secondtime);
$time2=unpack_windows_time( $secondtime );
($sec2, $min2, $hour2, $mday2, $mon2, $year2, $wday2, $yday2, $isdst2) = localtime($time2+46800);
$year2+=1900;
$mon2++;
printf "%2.2d/%2.2d/%d, %2.2d:%2.2d:%2.2d, ", $mon2,$mday2,$year2,$hour2,$min2,$sec2;
read STDIN, $thirdtime, 8;
$translated_firsttime=unpack(H16, $thirdtime);
$time3=unpack_windows_time( $thirdtime );
($sec3, $min3, $hour3, $mday3, $mon3, $year3, $wday3, $yday3, $isdst3) = localtime($time3+46800);
$year3+=1900;
$mon3++;
printf "%2.2d/%2.2d/%d, %2.2d:%2.2d:%2.2d, ", $mon3,$mday3,$year3,$hour3,$min3,$sec3;
ad path
read STDIN, $size, 8;
$translated_size=unpack(L, $size);
print "$translated_size\n";
}

As always, please feel free to leave commentary if you liked this article or want to call me on the carpet for some inaccuracy.

Share:
TwitterLinkedInFacebook
Copy url Url was copied to clipboard
Subscribe to SANS Newsletters
Receive curated news, vulnerabilities, & security awareness tips
United States
Canada
United Kingdom
Spain
Belgium
Denmark
Norway
Netherlands
Australia
India
Japan
Singapore
Afghanistan
Aland Islands
Albania
Algeria
American Samoa
Andorra
Angola
Anguilla
Antarctica
Antigua and Barbuda
Argentina
Armenia
Aruba
Austria
Azerbaijan
Bahamas
Bahrain
Bangladesh
Barbados
Belarus
Belize
Benin
Bermuda
Bhutan
Bolivia
Bonaire, Sint Eustatius, and Saba
Bosnia And Herzegovina
Botswana
Bouvet Island
Brazil
British Indian Ocean Territory
Brunei Darussalam
Bulgaria
Burkina Faso
Burundi
Cambodia
Cameroon
Cape Verde
Cayman Islands
Central African Republic
Chad
Chile
China
Christmas Island
Cocos (Keeling) Islands
Colombia
Comoros
Cook Islands
Costa Rica
Croatia (Local Name: Hrvatska)
Curacao
Cyprus
Czech Republic
Democratic Republic of the Congo
Djibouti
Dominica
Dominican Republic
East Timor
East Timor
Ecuador
Egypt
El Salvador
Equatorial Guinea
Eritrea
Estonia
Ethiopia
Falkland Islands (Malvinas)
Faroe Islands
Fiji
Finland
France
French Guiana
French Polynesia
French Southern Territories
Gabon
Gambia
Georgia
Germany
Ghana
Gibraltar
Greece
Greenland
Grenada
Guadeloupe
Guam
Guatemala
Guernsey
Guinea
Guinea-Bissau
Guyana
Haiti
Heard And McDonald Islands
Honduras
Hong Kong
Hungary
Iceland
Indonesia
Iraq
Ireland
Isle of Man
Israel
Italy
Jamaica
Jersey
Jordan
Kazakhstan
Kenya
Kiribati
Korea, Republic Of
Kosovo
Kuwait
Kyrgyzstan
Lao People's Democratic Republic
Latvia
Lebanon
Lesotho
Liberia
Liechtenstein
Lithuania
Luxembourg
Macau
Macedonia
Madagascar
Malawi
Malaysia
Maldives
Mali
Malta
Marshall Islands
Martinique
Mauritania
Mauritius
Mayotte
Mexico
Micronesia, Federated States Of
Moldova, Republic Of
Monaco
Mongolia
Montenegro
Montserrat
Morocco
Mozambique
Myanmar
Namibia
Nauru
Nepal
Netherlands Antilles
New Caledonia
New Zealand
Nicaragua
Niger
Nigeria
Niue
Norfolk Island
Northern Mariana Islands
Oman
Pakistan
Palau
Palestine
Panama
Papua New Guinea
Paraguay
Peru
Philippines
Pitcairn
Poland
Portugal
Puerto Rico
Qatar
Reunion
Romania
Russian Federation
Rwanda
Saint Bartholemy
Saint Kitts And Nevis
Saint Lucia
Saint Martin
Saint Vincent And The Grenadines
Samoa
San Marino
Sao Tome And Principe
Saudi Arabia
Senegal
Serbia
Seychelles
Sierra Leone
Sint Maarten
Slovakia
Slovenia
Solomon Islands
South Africa
South Georgia and the South Sandwich Islands
South Sudan
Sri Lanka
St. Helena
St. Pierre And Miquelon
Suriname
Svalbard And Jan Mayen Islands
Swaziland
Sweden
Switzerland
Taiwan
Tajikistan
Tanzania
Thailand
Togo
Tokelau
Tonga
Trinidad And Tobago
Tunisia
Turkey
Turkmenistan
Turks And Caicos Islands
Tuvalu
Uganda
Ukraine
United Arab Emirates
United States Minor Outlying Islands
Uruguay
Uzbekistan
Vanuatu
Vatican City
Venezuela
Vietnam
Virgin Islands (British)
Virgin Islands (U.S.)
Wallis And Futuna Islands
Western Sahara
Yemen
Yugoslavia
Zambia
Zimbabwe

By providing this information, you agree to the processing of your personal data by SANS as described in our Privacy Policy.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Tags:
  • Digital Forensics and Incident Response

Related Content

Blog
CTI_Blog_Image.png
Incident Response & Threat Hunting, Digital Forensics and Incident Response
January 23, 2023
A Visual Summary of SANS CTI Summit 2023
Check out these graphic recordings created in real-time throughout the event for SANS Cyber Threat Intelligence Summit 2023
370x370-person-placeholder.png
Alison Kim
read more
Blog
FOR577.png
Digital Forensics and Incident Response
September 22, 2022
NEW SANS DFIR COURSE IN DEVELOPMENT | FOR577: LINUX Incident Response & Analysis
FOR577: Linux Incident Response & Analysis course teaches how Linux systems work and how to respond and investigate attacks effectively.
Viv_Ross_370x370.png
Viviana Ross
read more
Blog
Untitled_design-43.png
Digital Forensics and Incident Response, Cybersecurity and IT Essentials, Industrial Control Systems Security, Purple Team, Open-Source Intelligence (OSINT), Penetration Testing and Red Teaming, Cyber Defense, Cloud Security, Security Management, Legal, and Audit
December 8, 2021
Good News: SANS Virtual Summits Will Remain FREE for the Community in 2022
They’re virtual. They’re global. They’re free.
370x370-person-placeholder.png
Emily Blades
read more
  • Register to Learn
  • Courses
  • Certifications
  • Degree Programs
  • Cyber Ranges
  • Job Tools
  • Security Policy Project
  • Posters & Cheat Sheets
  • White Papers
  • Focus Areas
  • Cyber Defense
  • Cloud Security
  • Cybersecurity Leadership
  • Digital Forensics
  • Industrial Control Systems
  • Offensive Operations
Subscribe to SANS Newsletters
Receive curated news, vulnerabilities, & security awareness tips
United States
Canada
United Kingdom
Spain
Belgium
Denmark
Norway
Netherlands
Australia
India
Japan
Singapore
Afghanistan
Aland Islands
Albania
Algeria
American Samoa
Andorra
Angola
Anguilla
Antarctica
Antigua and Barbuda
Argentina
Armenia
Aruba
Austria
Azerbaijan
Bahamas
Bahrain
Bangladesh
Barbados
Belarus
Belize
Benin
Bermuda
Bhutan
Bolivia
Bonaire, Sint Eustatius, and Saba
Bosnia And Herzegovina
Botswana
Bouvet Island
Brazil
British Indian Ocean Territory
Brunei Darussalam
Bulgaria
Burkina Faso
Burundi
Cambodia
Cameroon
Cape Verde
Cayman Islands
Central African Republic
Chad
Chile
China
Christmas Island
Cocos (Keeling) Islands
Colombia
Comoros
Cook Islands
Costa Rica
Croatia (Local Name: Hrvatska)
Curacao
Cyprus
Czech Republic
Democratic Republic of the Congo
Djibouti
Dominica
Dominican Republic
East Timor
East Timor
Ecuador
Egypt
El Salvador
Equatorial Guinea
Eritrea
Estonia
Ethiopia
Falkland Islands (Malvinas)
Faroe Islands
Fiji
Finland
France
French Guiana
French Polynesia
French Southern Territories
Gabon
Gambia
Georgia
Germany
Ghana
Gibraltar
Greece
Greenland
Grenada
Guadeloupe
Guam
Guatemala
Guernsey
Guinea
Guinea-Bissau
Guyana
Haiti
Heard And McDonald Islands
Honduras
Hong Kong
Hungary
Iceland
Indonesia
Iraq
Ireland
Isle of Man
Israel
Italy
Jamaica
Jersey
Jordan
Kazakhstan
Kenya
Kiribati
Korea, Republic Of
Kosovo
Kuwait
Kyrgyzstan
Lao People's Democratic Republic
Latvia
Lebanon
Lesotho
Liberia
Liechtenstein
Lithuania
Luxembourg
Macau
Macedonia
Madagascar
Malawi
Malaysia
Maldives
Mali
Malta
Marshall Islands
Martinique
Mauritania
Mauritius
Mayotte
Mexico
Micronesia, Federated States Of
Moldova, Republic Of
Monaco
Mongolia
Montenegro
Montserrat
Morocco
Mozambique
Myanmar
Namibia
Nauru
Nepal
Netherlands Antilles
New Caledonia
New Zealand
Nicaragua
Niger
Nigeria
Niue
Norfolk Island
Northern Mariana Islands
Oman
Pakistan
Palau
Palestine
Panama
Papua New Guinea
Paraguay
Peru
Philippines
Pitcairn
Poland
Portugal
Puerto Rico
Qatar
Reunion
Romania
Russian Federation
Rwanda
Saint Bartholemy
Saint Kitts And Nevis
Saint Lucia
Saint Martin
Saint Vincent And The Grenadines
Samoa
San Marino
Sao Tome And Principe
Saudi Arabia
Senegal
Serbia
Seychelles
Sierra Leone
Sint Maarten
Slovakia
Slovenia
Solomon Islands
South Africa
South Georgia and the South Sandwich Islands
South Sudan
Sri Lanka
St. Helena
St. Pierre And Miquelon
Suriname
Svalbard And Jan Mayen Islands
Swaziland
Sweden
Switzerland
Taiwan
Tajikistan
Tanzania
Thailand
Togo
Tokelau
Tonga
Trinidad And Tobago
Tunisia
Turkey
Turkmenistan
Turks And Caicos Islands
Tuvalu
Uganda
Ukraine
United Arab Emirates
United States Minor Outlying Islands
Uruguay
Uzbekistan
Vanuatu
Vatican City
Venezuela
Vietnam
Virgin Islands (British)
Virgin Islands (U.S.)
Wallis And Futuna Islands
Western Sahara
Yemen
Yugoslavia
Zambia
Zimbabwe

By providing this information, you agree to the processing of your personal data by SANS as described in our Privacy Policy.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
  • © 2023 SANS™ Institute
  • Privacy Policy
  • Contact
  • Careers
  • Twitter
  • Facebook
  • Youtube
  • LinkedIn