homepage
Open menu
Go one level top
  • Train and Certify
    • Overview
    • Get Started in Cyber
    • Courses
    • GIAC Certifications
    • Training Roadmap
    • OnDemand
    • Live Training
    • Summits
    • Cyber Ranges
    • College Degrees & Certificates
    • Scholarship Academies
    • NICE Framework
    • Specials
  • Manage Your Team
    • Overview
    • Group Purchasing
    • Why Work with SANS
    • Build Your Team
    • Hire Cyber Talent
    • Team Development
    • Private Training
    • Security Awareness Training
    • Leadership Training
    • Industries
  • Resources
    • Overview
    • Internet Storm Center
    • White Papers
    • Webcasts
    • Tools
    • Newsletters
    • Blog
    • Podcasts
    • Posters & Cheat Sheets
    • Summit Presentations
    • Security Policy Project
  • Focus Areas
    • Cyber Defense
    • Cloud Security
    • Digital Forensics & Incident Response
    • Industrial Control Systems
    • Cyber Security Leadership
    • Offensive Operations
  • Get Involved
    • Overview
    • Join the Community
    • Work Study
    • Teach for SANS
    • CISO Network
    • Partnerships
    • Sponsorship Opportunities
  • About
    • About SANS
    • Our Founder
    • Instructors
    • Mission
    • Diversity
    • Awards
    • Contact
    • Frequently Asked Questions
    • Customer Reviews
    • Press
  • 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. Uncident Response
Mike Cloppert

Uncident Response

February 7, 2010

A while ago, I was asked to assist in responding to a security problem on a client's network. A major vulnerability was reported on a website that involved failure of the primary authentication and access control mechanism. So severe was the vulnerability that not only could one user view another's PII, but complete authentication circumvention was itself trivial! I was tasked with assessing what, if any, impact had resulted from this exposure. This probably sounds familiar to many security analysts: a vulnerability was discovered, what compromise resulted from it?

These cases turn classic incident response on its head. We are trained, and often work, on issues where a compromise is discovered, from which analysis reveals a vulnerability. Here, we have the opposite. One immediate difference is clear: when there is a compromise, some vulnerability was necessarily exploited. However, the result of a vulnerability investigation is not so clear. Our normal incident response techniques fall apart in this case. I'm coining a term: I call this uncident response. Here I'll outline a few properties of these investigations and rules of thumb to deal with this sort of investigation.

  • Property 1 (by definition): Uncident response is analysis that begins with a vulnerability and attempts to discover a compromise based on how the vulnerability is exploited.
  • Property 2: It is impossible to prove that no compromise occurred. Such conclusions can only be made through inductive reasoning, which is generalizing from a set of facts. Discovering a compromise can be conclusive because in such cases, one uses deductive reasoning to show that based on empirical evidence collected, it logically follows that the vulnerability was exploited. This duality relates to the notion of innocent until proven guilty in U.S. law: only given complete omniscience for the actions that took place and the causality behind them can one conclusively say nothing happened. This rarely, if ever, is the case. Put another way, absence of evidence is not evidence of absence.
  • Property 3: Conclusions will always be conjecture or, at best, made with a margin of error. This is reality based on Property 2. Even if numerous compromises are discovered, one cannot say with complete certainty that no additional compromises occurred. This will nearly always be a subjective assessment based on professional experience of the analyst.
  • Property 4: The confidence of conclusions will be limited by the data and time available to the analyst. No logs = no conclusions. Few logs = poor confidence in conclusions. Etc...

Considering these properties of "uncident response," based on my own experience, I offer the following suggestions so you can provide quality analysis and keep yourself out of trouble:

  1. Set expectations. Make sure all parties involved completely understand the properties above.
  2. Limit scope. In my case above, the vulnerability was in a web application that exposed PII. The digital forensic investigation demanded by the client was wasteful and unnecessary, and illustrated a failure to understand the issue on their part, or to communicate the issue on mine/ours.
  3. Set reasonable time limits for analysis. The analysis could in some cases go on forever. At the same time, confidence in the analysis will be artificially limited if insufficient time is available. Try to predict the point of diminishing returns, and wrap up analysis at that point.
  4. Clearly distinguish between deductive and inductive conclusions, the observed and the interpreted.
  5. Properly qualify all conclusions. Use words like "believe" and explicitly state confidence intervals. Exercise extreme caution when using words like "fact," "true," and "false;" limit them to deductive reasoning. Absolutely avoid absolutes.
  6. Refuse to provide conclusions if insufficient time or data is available to make statements you are comfortable with. This is sometimes very difficult to do, because those in charge want conclusions and will exert pressure. Professional integrity, ethics, and the best interests of those potentially victimized dictate that you stand firm on this point, however. Providing conclusions that are nothing more than guesses puts you at risk. Responsible parties need to learn that sometimes the only correct response is "I do not know."

In a later entry I will discuss how I analyzed the limited data available to me in the case above, and make some measured statements that the client was happy with. The story ended well - with high confidence I was able to conclude that no widespread exploitation of the vulnerability occurred.

Michael is a senior member of Lockheed Martin's Computer Incident Response Team. He has lectured for various audiences including SANS, IEEE, and the annual DC3 CyberCrime Convention, and teaches an introductory class on cryptography. His current work consists of security intelligence analysis and development of new tools and techniques for incident response. Michael holds a BS in computer engineering, an MS in computer science, has earned GCIA (#592) and GCFA (#711) gold certifications alongside various others, and is a professional member of ACM and IEEE.

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
Kingdom of Saudi Arabia
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
Senegal
Serbia
Seychelles
Sierra Leone
Sint Maarten
Slovakia (Slovak Republic)
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

Tags:
  • Digital Forensics and Incident Response

Related Content

Blog
SANS_DFIR_Justify_Your_Training.png
Digital Forensics and Incident Response
January 20, 2022
SANS DFIR courses - Justify your training
Use these justification letter templates to share the key details of this training and certification opportunities with your boss.
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 Ethical Hacking, 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.
Emily Blades
read more
Blog
Digital Forensics and Incident Response
June 4, 2010
WMIC for incident response
Earlier this week, I posted about using psexec during incident response. I mentioned at the end of that post that I've been using WMIC in place of psexec and that I'd have more on that later. This post, is a follow up to the psexec post. WMIC Prompted by the excellent work of Ed Skoudis and his...
370x370_Mike-Pilkington.jpg
Mike Pilkington
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
  • Cyber Security 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
Kingdom of Saudi Arabia
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
Senegal
Serbia
Seychelles
Sierra Leone
Sint Maarten
Slovakia (Slovak Republic)
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
  • © 2022 SANS™ Institute
  • Privacy Policy
  • Contact
  • Careers
  • Twitter
  • Facebook
  • Youtube
  • LinkedIn