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. 6 Hex Editors for Malware Analysis
Lenny_Portrait_New_370x370.jpg
Lenny Zeltser

6 Hex Editors for Malware Analysis

September 29, 2010

Hex editors allow examining and modifying a file at the low-level of bytes and bits, usually representing the file's contents in hexadecimal form. Some editors distinguish themselves at helping the user derive meaning from the examined file, extracting ASCII and Unicode contents, searching for patterns, recognizing common structures, and so on. There are lots of hex editors out there; I want to mention a few that I find particularly useful for analyzing malware and examining malicious document files.

FileInsight

FileInsight is a free hex editor from McAfee Labs that runs on Microsoft Windows (download zip file). As expected, it can perform standard hex editor duties, such as viewing and editing file contents in a hex form, but it also does more than that.

FileInsight is able to parse the structure of compiled Windows executables (PE files) and binary Microsoft Office (OLE) documents. Furthermore, the tool has a built-in x86 disassembler: simply point the cursor at the area of the file you want to treat as code, and the tools will show you the corresponding assembly instructions. The disassembler is especially helpful when looking at shellcode embedded in malicious files.

FileInsight includes numerous other analyst-friendly features, such as the ability to import data structure declarations, HTML syntax highlighting, and tools for decoding various data obfuscation methods (xor, add, shift, Base64, etc.). FileInsight also allows you to automate actions using JavaScript and Python.

The tool's biggest weakness is, perhaps, its inability to open very large files. For instance, when attempting to load a 512MB file, FileInsight produced a "Failed to open document" error. Also, FileInsight does not support searching for Unicode-encoded strings that look like ASCII strings.

fileinsight.png

Hex Editor Neo

Hex Editor Neo is available as free and commercial versions for Microsoft Windows from HDD Software. Its freeware version provides typical hex editor features in a friendly and highly-customizable interface, but is not particularly impressive. However, unlike FileInsight, all versions of Hex Editor Neo can open very large files and allows user to look for ASCII and Unicode-encoded strings.

The features of Hex Editor Neo relevant to malware analysis are present in its commercial versions (see version comparison). For instance, the Standard version introduces the support for handling data manipulations, such as decoding, encrypting and deobfuscating using common algorithms. (Notably, these features are included for free in FileInsight.) The Professional version introduces support for viewing and editing local resources, such as NTFS streams, local disks, process memory and physical RAM. The Ultimate version includes scripting support and built-in disassemblers for x86, x64 and .NET code.

FileInsight is probably a better match than Hex Editor Neo for regular malware analysis use. However, Hex Editor Neo's commercial versions add value to the toolkit by supporting very large files, x64 and .NET disassembly, local resource editing, searching for Unicode strings and extensive customization support of its user interface.

hex-editor-neo.png

FlexHex

FlexHex is a powerful commercial hex editor from Heaventools Software that includes many features comparable to commercial versions of Hex Editor Neo, though FlexHex does not support scripting.

FlexHex only stands out from Hex Editor Neo in its ability to parse binary Microsoft Office (OLE) documents. However, FlexHex might get confused when attempting to parse some malicious OLE files, presenting a "The docfile has been corrupted" error. Overall, this is probably the weakest editor of those examined here from the perspective of a malware analyst.

flexhex1.png

010 Editor

010 Editor is a commercial hex editor for Microsoft Windows from SweetScape Software. Its core features are comparable to those of the commercial versions of Hex Editor Neo and FileHex: support for very large files, data manipulation, local resource editing, and so on. Like Hex Editor Neo, 010 Editor also supports scripting.

010 Editor shines in its ability to parse various file formats by using a large library of user-contributed templates. This makes it easier for the analyst to navigate various file formats, including Windows executables (PE files), Windows shortcut (LNK) files, Zip archives, Java Class files, and many more. Malware analysts will particularly appreciate the template for parsing PDF files that Didier Stevens created for 010 Editor. You can also download several user-submitted 010 Editor scripts from its website.

101-editor.png

Hiew

Hiew is a commercial hex editor by Eugene Suslikov for Microsoft Windows. It is a favorite among many malware researchers due to the powerful features for examining and editing the structure and contents of Windows executables (PE files) and Linux binaries (ELF files). Another very useful feature for reverse-engineering malicious programs is the tool's ability to disassemble and assemble x86 and x64. Hiew's disassembler even supports the ARM instruction set. Hiew can handle very large files and edit local logical and physical drives. It supports macros, scripts and even has an API set for additional extension and automation.

It works in a DOS-style console window and is generally unfriendly towards a new user, in comparison to the other hex editors I discussed so far. It's a powerful hex editor, but is not well-documented. For those who don't already know how to use it, it probably isn't the best tool to get started with, given the number of other powerful hex editors and disassemblers available.

hiew.png

Radare

Radare is a set of free tools for Unix platforms that include powerful hex editing capabilities. Radare's features are too numerous to list here, and include support for examining and tweaking Windows executables (PE files), Linux binaries (ELF files) and Java Class files, comparing binary files, as well as disassembling, reassembling and debugging code. The tool also includes shellcode generator, which is particularly relevant for those who analyze vulnerabilities and exploits. The capabilities of Radare are extensible and scriptable.

The drawback of Radare is that it is a command-line tool that is difficult to master. Fortunately, it includes rather extensive documentation. Radare is of particular interest for analysts who prefer working in Unix environments with command-line tools. (Radare is included in the REMnux distro for malware analysis.)

radare.png

Conclusion

We looked at several powerful hex editors that included features useful for analyzing malicious software. Of these, FileInsight stood out for its overall feature set that malware analysts find useful on regular basis. 010 Editor provided a large number of templates for parsing file, including PDF documents, and was highly customizable. FlexHex included support for parsing some binary Microsoft Office (OLE) files, but otherwise did not stand out. Hex Editor Neo expanded the toolkit by being able to disassemble x86, x64 and .NET code. Radare offered comprehensive, but hard-to-use command-line capabilities for Unix platforms. Hiew included powerful features for tinkering with compiled executables, but was not-user friendly.

Hex EditorHighlighted FeaturesHighlighted Limitations
FileInsightBuilt-in x86 disassembler
Many data decoding methods
Scriptable
Parses PE and OLE formats
Free
Cannot handle very large files
Hex Editor NeoBuilt-in x86, x64, .NET disassembler
Many data decoding methods
Handles very large files
Scriptable
Highly-configurable interface
Advanced features in commerical version
FlexHexParses OLE format
Handles large files
Some data decoding methods
Not scriptable
Commercial
010 EditorParses many formats, including PE and PDF
Support for custom parsing templates
Many data decoding methods
Handles very large files
Scriptable
Commercial
HiewBuilt-in x86, x64, etc. disassembler
Built-in reassembler
Handles very large files
Many data decoding methods
Commercial
Hard to use
Not well-documented
RadareBuilt-in x86, x64, etc. disassembler
Built-in reassembler
Handles very large files
Many data decoding methods
Free
Hard to use

Personally, FileInsight and 010 Editor offer the most value for my malware analysis work on Windows and Radare on Unix, leaving FlexHex, Hex Editor Neo and Hiew in the "nice-to-have" category. Of course, everyone has his or her own preferences. What's your favorite hex editor?

Lenny Zeltser focuses on safeguarding customers' IT operations at NCR Corporation. He also teaches how to analyze malware at SANS Institute. Lenny is active on Twitter and writes a security blog.

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