Detection of Obscene or Pornographic Images from Emails

Detection of Obscene Images through Skin Tone Analysis

Case Overview

In my past 10 years of profession as a digital forensic investigator, it was first time that I handled a personal case. The case involved one of my close friends and his sister who happened to be the victim of sexual coercion. It was her boyfriend with whom she spent most of her time, took photographs, shared them on social media and had a good relationship. It was later found that he along with his friends, sexually assaulted her, took pictures without her consent and spread them online.

Objectives

To attain concrete evidence against the accused and his four friends as; intending to insult the modesty of a woman, intrusion into the privacy of a woman through cyber space.

Motive

The primary motive of the crime, concluded to be 'intrusion into the privacy of a woman through cyber space'.

Modus Operandi

Sexual Coercion and compelling another individual to uphold sexual activities against ones will.
The suspect circulated the morphed Pornographic Images through his Yahoo mail, among his friends.
Manipulation, Intimidation, threats, and blackmailing for the personal needs.

Solution

He was in need of an expert in cybercrime investigation having deep knowledge of email forensics. I carried out the following actions in order to proceed further with the investigation process.

Acquisition of the primary email account involved (of boyfriend) – the primary suspect.
Acquisition of the secondary email accounts involved (that of friends) – secondary suspects.

Challenges

The challenges that I have faced during this investigation process was that

Viewing and analyzing bulk amount of emails and attachments from his account.
Sorting of emails with attachments from the ones without attachments.
Filtering of the attachment based emails to find out only those with objectionable images of the victim.

The Procedure

Documentation

The documentation phase was very simple since I was dealing with a private case for my friend. Even though it was a personal case as part of professional forensic investigation, I documented the case evidence both; before and after investigation process, to support my investigation in the court of law.

Tool used

MailXaminer: It is the only one tool that I have used throughout the investigation stages of this case. It is a multipurpose email forensic analysis tool with excellent features to carve out evidences from the bulk of emails. The Skin Tone Analysis feature of MailXaminer enabled me to sort out the emails with images shared by the suspects without the consent of the victim. This feature enabled me to sort out the emails with photographic images as attachments.

Strategies

Various stages that I have carried during this investigation process includes

Studied The Case – I have studied the case in detailed, analyzed the nature of the suspect and his friends.
Evidence Collection – The email accounts credentials of the suspect was collected using advanced forensic tools and various other details from the victim.
Verification & Analysis – An exhaustive verification was done with the collected evidences and documents to prove the crime during the investigation process. Using Skin Tone Analysis feature of the tool I sorted out the emails with objectionable images from the bulk.
Report Generation – A full report of the entire case describing the stages of investigation and the evidence analysis was done.

Supportive Law

The law that supports the case was registered under IPC Section 509- Word, gesture or act intended to insult the modesty of a woman.

Results Obtained

I could complete the investigation for my friend within a short time limit.

Email account were scanned and analyzed for evidence within short time.
Out of 1000+ emails in the accounts the required emails were scanned reported accurately.
The accused were charged for the proven guilty that had been claimed at them.

Case Study