Protecting Children’s Personal Information: Using Contextual Integrity Theory to Examine

Information Boundary on Mobile Devices

Ying Chen*, Sencun Zhu*, Yilu Zhou+, Heng Xu**The Pennsylvania State University

+Fordham University

Children’s Privacy Risk with Mobile Use

• 25% of toddlers used their parents’ smartphones in 2011

• 48% of American children aged between 6 and 12 want iPad for Christmas gift

• Nearly 10% children get first mobile phone by the age 5

Children’s Privacy Risk with Mobile Use

• Children’s personal information (CPI) can be easily leaked via mobile use

• Sharing CIP on mobile devices to third-parties exposes children to risks such as cyber-solicitation

• Only 13% of mobile apps have privacy policies regarding collection and distribution of children’s personal information

Parents Unaware of Privacy Risks

Let strangers know these information is dangerous for

children

• Where are you at this moment?

• How can I bond with you?

Contextual Integrity Theory as a Theoretical Framework

• We use the contextual integrity theory to examine information boundaries on mobile platforms

• We aim at developing quantitative measures of privacy risks on children’s mobile apps

• We propose context-based mobile privacy controls, and perform a case study to examine the information boundaries among the top 49 coloring apps

Contextual Integrity Theory as a Theoretical Framework

• Nissenbaum’s theory of contextual integrity argues that privacy concerns are not absolute but largely depend on the context.

• In general, contextual integrity conceptualizes privacy as the flow of information of a certain type (attributes) about a subject from a sender to a recipient, governed by a particular transmission principle in a given context.

O Actors-recipients (whom)

O UsersO Apps/websitesO Advertising networksO Analytic third parties

O Attributes (what)O LocationO ContactO CalendarO AudioO CameraO Transmission

principles (how)O Privacy policy?O Require login to

use the service?O Collect

unnecessary attributes?

O Context (where)O Temporal statusO LocationO Surrounding roles

Four Elements

Case Study

• Exploiting contextual integrity theory to • Establish a context-based access control

mechanism on mobile platforms• Quantitatively measure privacy risks of

children’s mobile apps

Context-based Access Control on Mobile Platforms

• The safety level of disclosing CPI on mobile devices highly depends on the context

• When children use mobile devices in risky times, unprotected locations, or without guardians’ companion, mobile platforms should automatically limit the disclosure of CPI

• Rules can be designed on mobile platforms to limit disclosure of certain types of CPI under certain context

Quantitative Privacy Risk Measures on Mobile Apps

• Measure the privacy risk levels of mobile apps with three dimensions in contextual integrity:1. actors,

2. attributes, and

3. transmission principles

• We conducted an experiment to show how the proposed method can effectively measure apps’ privacy risks and help parents choose safe apps for their children.

Case study

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Noted: Bubble Size = # of violations of transmission princi-ples Bubble Label = App rank

Thanks!Protecting Children’s Personal Information:

Using Contextual Integrity Theory to Examine Information Boundary on Mobile Devices

Ying Chen, Sencun Zhu, Yilu Zhou, Heng Xu