This is a presentation I delivered to the Federal Defenders Program for the District of Indiana (N.D.) on December 18, 2013. It is a 6-hour CLE presentation covering the following topics: overview of the law of child pornography, methods of distribution, digital investigations, hash values, trial issues, and the ethics of client data.
TataKelola dan KamSiber Kecerdasan Buatan v022.pdf
2013-12-18 Digital Forensics and Child Pornography (inc. 1 hour ethics)
1. Digital Forensics and
Child Pornography
Frederick S. Lane
Federal Defenders Program, D. Ind. (N.D.)
Plymouth, IN
18 December 2013
www.FrederickLane.com
www.ComputerForensicsDigest.com
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2. Seminar Overview
• Introduction and Overview
• Digital Technology and CP
• Digital Investigations
• Hash Values and Image Integrity
• Defending Child Pornography
Cases
• The Ethics of Client Data
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3. Introduction and Overview
• Background and Expertise
• What Is Child
Pornography?
• Digital Technology and the
Spread of Child
Pornography
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4. Background and Expertise
• Attorney and Author of 7
Books
• Computer Forensics
Expert -- 15 years
• Over 100 criminal cases
• Lecturer on ComputerRelated Topics – 20+
years
• Computer user
(midframes, desktops,
laptops) – 35+ years
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5. What Is Child Pornography?
• Federal Laws
• State Laws
• Indiana CP Laws
• International Law
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6. Federal CP Laws
• 18 U.S.C. c. 110 – Sexual
Exploitation and Other Abuse
of Children
• 18 U.S.C. § 2251 – Production
• 18 U.S.C. § 2252 – Possession,
Distribution, and Receipt
• 18 U.S.C. § 2256 -- Definitions
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7. “Child Pornography”
18 U.S.C. § 2256(8): “any visual depiction, including
any photograph, film, video, picture, or computer or
computer-generated image or picture, whether made
or produced by electronic, mechanical, or other
means, of sexually explicit conduct, where—
(A) the production of such visual depiction
involves the use of a minor engaging in sexually
explicit conduct; [or]
(B) such visual depiction is a digital image,
computer image, or computer-generated image that is,
or is indistinguishable from, that of a minor engaging in
sexually explicit conduct; or
(C) such visual depiction has been created,
adapted, or modified to appear that an identifiable
minor is engaging in sexually explicit conduct.”
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8. Other Relevant Definitions
• “Minor” [18 U.S.C. § 2256(1)]: <18
• 18 U.S.C. § 2257: Record-keeping requirements
• “Sexually Explicit Conduct” [18 U.S.C. § 2256(2)(A)]:
• (i) sexual intercourse, including genital-genital, oral-genital, anal-genital,
or oral-anal, whether between persons of the same or opposite sex;
• (ii) bestiality;
• (iii) masturbation;
• (iv) sadistic or masochistic abuse; or
• (v) lascivious exhibition of the genitals or pubic area of any person.
• Slightly Different Definitions for Computer Images [18
U.S.C. § 2256(2)(B)]
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9. NCMEC
• “National Center for Missing and
Exploited Children”
• Created by Congress in 1984
• Child Recognition and
Identification System – database of
hash values of CP images
• Child Victim Identification
Program
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10. State CP Laws
• All 50 states have their own CP laws
• Age of minority varies: 16 (30
states); 17 (9 states); and 18 (12
states)
• Prosecution can be federal or state,
or both.
• Can include “harmful to minors”
standard (states only)
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11. Indiana CP Laws
• Ind. Code, tit. 35, art. 42, ch. 4, § 4 –
Child exploitation; possession of CP
• Ind. Cod, tit. 35, art. 49, chs. 1-3 –
Obscenity and Pornography
• Ind. Code § 35-49-3-1 – Distribution
is a Class D felony if person
depicted is or appear to be < 16.
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12. Ind. Code § 35-49-1-4, -9
•
“Minor”:
•
•
Anyone under age of 18 (increased penalties if individual is
or appears less than <16).
“Sexual Conduct”:
• (1) sexual intercourse or deviate sexual conduct;
• (2) exhibition of the uncovered genitals in the context of
masturbation or other sexual activity;
• (3) exhibition of the uncovered genitals of a person under
sixteen (16) years of age;
• (4) sado-masochistic abuse; or
• (5) sexual intercourse or deviate sexual conduct with an
animal.
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13. International CP Laws
• Over last 7 years, 100 countries
have adopted new CP laws
• 53 countries still have no CP law
at all
• International Center for Missing
and Exploited Children
• 2012 Child Pornography Model
Laws: http://bit.ly/19eWJPz
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14. End of Section One
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15. Digital Technology and CP
A Brief Background
Digital Production of CP
Digital Distribution of CP
Digital Consumption
(Receipt and Possession)
• Societal Changes
•
•
•
•
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16. A Brief Background
•
1978: Protection of Children Against Sexual
Exploitation Act
•
1982: New York v. Ferber – Upholding state
law banning child pornography
•
1984: Child Protection Act (prohibiting noncommercial distribution)
•
1992: Jacobson v. United States – Postal
Service entrapment
•
2000: Poehlman v. United States – FBI
entrapped defendant after lengthy email
correspondence
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17. Digital Production of CP
• Scanners
• Digital Cameras (still and
video)
• Cameraphones (dumb and
smart)
• Web cams
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18. Digital Distribution of CP
• One-to-One
• Sneakernet
• E-mail / Personal File-Sharing
• Instant Messaging / Chat Rooms
• One-to-Many
•
•
•
•
Newsgroups and Forums
Peer-to-Peer Networks
Torrent Networks / File-Hosting
Underground Web Sites
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19. Digital Consumption of CP
• Producer of CP may be in
possession without having
“received” it
• Defendant may be in “receipt” of
CP without “knowingly”
possessing it
• The challenges of determining
“intentionally” and “knowingly” in
the context of Internet activity
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20. Societal Changes
• Computers and the
Internet
• The Democratization of
Porn Production
• “Porn Chic”
• The “Selfie”
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21. End of Section Two
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22. Digital Investigations
• Discovery of Possible Child
Pornography
• The Role of IP Addresses
• Intro to Computer
Forensics
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23. Discovery of Possible CP
•
•
•
•
•
Angry Spouse or Girlfriend
Geek Squads
Chat Rooms
Hash Flags
P2P and Torrent
Investigations
• Server or Payment Logs
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24. Overview of IP Addresses
• Assigned to Every InternetConnected Device
• Two Flavors:
• IPv4: 196.172.0.1
• IPv6:
2001:0db8:85a3:0042:1000:8a2
e:0370:7334
• Leading to “Internet of Things”
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25. IP → Physical Address
• Ranges of IP Addresses
Assigned to ISPs by Internet
Assigned Numbers Authority
• Online Tools to Look Up ISP
• Dynamic vs. Static
• Subscriber Records Show
Date, Time, IP Address,
Limited Activity
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26. Limitations of IP Addresses
• Links Online Activity to
Device, Not Necessarily a
Specific User
• Data May Not Be Available
from ISP
• Possibility of War-Dialing
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28. Increasingly Specialized
• Computer Forensics
• Windows
• Mac OS
• Linux
• Network Forensics
• Mobile Forensics
• Dozens of Mobile OSs
• Hundreds of Models
• Cloud Forensics
• Many Questions, No Clear Answers
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30. A Typical Forensics Report
• There should be at least two
reports:
•
•
•
•
•
• Acquisition
• Evaluation of Evidence
Bowdlerized
Detailed procedures
Hash value checks
Bookmarks of possible contraband
Evidence of user ID
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31. End of Section Three
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32. Hash Values & Image Integrity
• Not Your Mother’s Hash
• The Role of Hash Values in
Computer Forensics
• The Growing Use of Hash
Flags
• P2P Investigations Using Hash
Values
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33. Not Your Mother’s Hash
• Cryptograhic Hash Values
• Relatively Easy to Generate
• Extremely Difficult to Determine
Original Data from Hash Value
• Extremely Difficult to Change Data
without Changing Hash
• Extremely Unlikely that Different Data
Will Produce the Same Hash Value
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34. Complex Explanation (1)
• The word DOG can be represented in
different ways:
•
•
Binary: 010001000110111101100111
Hexadecimal: 646f67
• A hash algorithm converts the
hexadecimal value to a fixed-length
hexadecimal string.
•
•
SHA-1:
e49512524f47b4138d850c9d9d85972927
281da0
MD5:
06d80eb0c50b49a509b49f2424e8c805
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35. Complex Explanation (2)
• Changing a single letter changes
each value.
• For instance, the word COG
produces the following values:
• Binary: 010000110110111101100111
• Hexadecimal: 436f67
• SHA-1:
d3da816674b638d05caa672f60f381ff
504e578c
• MD5:
01e33197684afd628ccf82a5ae4fd6ad
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37. Evidence Integrity
•
Acquisition Hashes
•
Creation of Mirror Images
•
Verification of Accuracy of Mirror Images
•
Use of “Known File Filter”
•
•
•
Hashkeeper
National Software Reference Library
NCMEC CVIP Database
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38. Growing Use of Hash Flags
• Child Protection and Sexual Predator
Act of 1998
• 2008: ISPs Agree to Block Access to
Known Sources of CP and to Scan for
NCMEC Hash Values
• SAFE Act: Requires ISPs and OSPs to
Turn Over Subscriber Info If Known
CP Is Identified
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39. P2P Hash Values
• Basic Operation of Peer-toPeer Networks
• Decentralized Distribution
• Gnutella and eDonkey
• Client Software
• Hash Values Associated with
Each File
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40. Automated P2P Searches
• “Peer Spectre” or “Nordic Mule”
Scans for IP Addresses of Devices
Offering to Share Known CP Files
• IP Addresses Are Stored by TLO in
Child Protection System
• Officers Conduct “Undercover”
Investigations by Reviewing
Spreadsheets of Hits in CPS
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41. Growing Defense Concerns
• No Independent Examination of
Proprietary Software
• Very Little Information Regarding TLO or
CPS
• Peer Spectre May Generate False Hits Due
to Normal Operation of P2P Clients
• Search Warrant Affidavits Fail to Mention
Role of TLO or CPS
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42. End of Section Four
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43. Defending CP Cases
• Determining Age of Person
Depicted
• Pre-Trial Issues
• Trial Issues
• Typical Defenses in CP Cases
[Some More Viable than Others]
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44. Determining Age
Is expert testimony need?
Tanner Stage: Outmoded?
Role of environmental factors
Bait and switch
Defendant’s subjective belief
is irrelevant
• Prosecutors prefer clear cases
•
•
•
•
•
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45. Pre-Trial Issues
• Retaining a Defense Expert
• Deposition of Government
Experts
• Motion(s) to Produce
• Motion(s) to Suppress or
in limine
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46. Trial Issues
• Should There Be a
Trial?
• Motion(s) in limine
• Cross-Examination of
Government Expert
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47. Typical Defenses (1)
• Lack of Possession or Receipt
• Mere Browsing
• The Phantom Hash
• Accident or Lack of Intent
• Ignorance or Mistake as to Age
• Not a Real Child / Morphed /
Computer-Generated
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48. Typical Defenses (2)
• Multiple Persons with Access
to Device
• Used Equipment with PreExisting CP
• Viral Infection
• Planting of Evidence by Spouse
or Police
• Entrapment
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49. End of Section Five
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50. The Ethics of Client Data
• Client Data in the Office
• Client Data in the Home
• Client Data in the Cloud
• Client Metadata
• CP-Specific Issues
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51. Client Data in the Office
• Physical Security
•
Locks
•
Supervision of Visitors
• Electronic Security
•
Logins and Passwords
•
Screensavers
• Authorized Users
• Backup(s)
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52. Client Data in the Home
• Should It Even Be There?
• How Does It Get There?
• Physical Security
• Encryption?
• Who Has Access to the
Device(s)?
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53. Communicating with Clients
• Is It Ethical to Use E-Mail?
• Understanding How E-Mail
Works
• Ethics of Automatic Robot
Scanning
• Is HTTPS Sufficient?
• Secure E-Mail Alternatives
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54. Client Data in the Cloud
• Brief Overview of Types of
Cloud Services
• The Ethics of Cloud Storage
• The Ethics of Cloud
Collaboration
• Discovery in the Cloud
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55. The Ethics of Metadata
• What Is Metadata?
• Who Knows What Metadata Lurks in a
File?
• Don’t Accidentally Release Metadata
• Can I Use Someone Else’s
Accidentally-Released Metadata?
• Should I Affirmatively Ask for
Metadata During Discovery, and Can I
Get It?
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56. CP-Specific Issues
• Rule #1: Do Not Obstruct Justice
• Rule #2: Minimize Handling and
Isolate Device(s)
• Rule #3: If Identifiable Victim, Review
Mandatory Reporting Requirements
[Ind. Code § 31-33-5-1]
• Rule #4: Never Re-Distribute
• Rule #5: Hire an Expert
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57. End of Section Six
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58. Slides and Contact Info
• Download a PDF of slides
from:
SlideShare.net/FSL3
• E-mail or Call Me:
FSLane3@gmail.com
802-318-4604
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59. Digital Forensics and
Child Pornography
Frederick S. Lane
Federal Defenders Program, D. Ind. (N.D.)
Plymouth, IN
18 December 2013
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