=Paper= {{Paper |id=Vol-1873/IWPE17_paper_14 |storemode=property |title=Assessing Privacy in Social Media Aggregators |pdfUrl=https://ceur-ws.org/Vol-1873/IWPE17_paper_14.pdf |volume=Vol-1873 |authors=Gaurav Misra,Jose M. Such,Lauren Gill |dblpUrl=https://dblp.org/rec/conf/sp/MisraSG17 }} ==Assessing Privacy in Social Media Aggregators== https://ceur-ws.org/Vol-1873/IWPE17_paper_14.pdf
      Assessing Privacy in Social Media Aggregators
                   Gaurav Misra                                  Jose M. Such                                   Lauren Gill
              Security Lancaster                          Department of Informatics         School of Computing and Communications
   School of Computing and Communications                King’s College London, UK                  Lancaster University, UK
           Lancaster University, UK                      Email: jose.such@kcl.ac.uk               Email: l.gill2@lancaster.ac.uk
        Email: g.misra@lancaster.ac.uk




   Abstract—Social Media Aggregator (SMA) applications                   related to better utilization of the often limited resources
present a platform enabling users to manage multiple Social              (RAM, CPU power and battery) of the mobile phone itself.
Networking Sites (SNS) in one convenient application, which              Indeed, many SMAs clearly convey this to potential customers
results in a unique concentration of data from several SNS
accounts in addition to the user’s mobile phone data available to        as an advantage and a selling point3 .
them. We describe a three-step methodology to assess how privacy            While it is clear that SMAs can be beneficial for users, they
is considered in these applications: 1) We inspect the mobile data       also potentially introduce severe privacy risks for users. Users
and social media data; 2) we study any privacy policies and              are meant to use SMAs to combine multiple social media
their compliance with respect to distributor’s vetting policies;
                                                                         accounts and all the activity is routed through a single SMA.
and 3) we perform a qualitative assessment of traceability
between privacy policies and the actual transparency and control         This is different from using separate applications for different
mechanisms offered to users by the apps’ interfaces. We then             social media accounts as a user’s Facebook application, for
present the results we obtained for 13 popular SMAs from 3 app           example, cannot access their Twitter activity unless an explicit
stores, showing a variation in data accessed by the individual           link is made by the user. Such a link between various social
applications, an absence of privacy policies for 5 of the SMAs
                                                                         media profiles is implicit in the case of SMAs. Moreover,
evaluated, and a lack of traceability between privacy policies and
transparency and control of interface operations. After this, we         this information about social media activity is augmented with
report our experiences using the methodology and the lessons             mobile device data such as GPS location, contact lists, camera,
learned, together with potential future work to improve the              etc. Given this potential threat to the privacy of social media
methodology and its potential to also assess privacy in other            users, it is essential to take a closer look at the transparency
mobile applications that also connect with social media.
                                                                         and control mechanisms offered by these applications. This
   Index Terms—Social Media Aggregators, Social Media Privacy
                                                                         understanding will help further in-depth analysis of gaps in
                         I. I NTRODUCTION                                policy and technology which are required to be overcome in
                                                                         order to safeguard user privacy and enable appropriate usage
   It is evident that our engagement with Social Networking              of SMAs.
Sites (SNS) is becoming ever more ingrained in our daily lives.
                                                                            In this paper, we describe a three-step methodology to assess
This has been, in part, facilitated by the spectacular growth of
                                                                         how privacy is considered in these applications. We begin by
mobile social networking, which has a worldwide penetration
                                                                         looking at the Data Permissions requested by SMAs. This
of 23% (1.7 billion). This proliferation of mobile devices have
                                                                         includes both mobile data as well as social media data of
enabled the users to access social media accounts with more
                                                                         the user. We then check whether the SMAs have relevant
ease and convenience. This is demonstrated by the huge surge
                                                                         Privacy Policies or other related documentation which explain
in usage of social applications on mobile platform to the extent
                                                                         the collection, usage and purpose of the user data being
that an estimated 80% of time spent on social media is using
                                                                         collected by them. Then, we qualitatively analyze the privacy
mobile applications1 .
                                                                         policies and perform a Traceability Analysis where we evaluate
   This shift towards the mobile platform for social media ac-
                                                                         whether the interface provided to the users are congruent
tivity has led to the development of Social Media Aggregators
                                                                         with documented policies to evaluate how transparent data
(SMAs) which enable users to access all of their social media
                                                                         collection is and whether users have a control over the amount
accounts from a single application. This is partly driven by the
                                                                         and nature of data being collected.
fact that users are often found to have accounts on multiple
                                                                            We report the results we obtained for 13 popular SMAs
Social Networking Sites (SNSs)2 . It can be quite attractive to
                                                                         from 3 app stores, showing: a variety in the data accessed,
users to use SMAs, a single application for all social media
                                                                         especially when it comes to mobile data; a partial lack of
accounts, compared to installing separate applications for all
                                                                         privacy policies (5 out of the 13 SMAs do not have privacy
their social media sites. An additional attraction of installing
                                                                         policies); and that a substantial proportion (45%) of SMAs
a single SMA replacing all social media applications is also
                                                                         show Broken traceability between policy documentation and
 1 http://marketingland.com/facebook-usage-accounts-1-5-minutes-spent-
mobile-171561                                                              3 https://play.google.com/store/apps/details?id=com.friends.
 2 http://www.pewinternet.org/2013/12/30/social-media-update-2013/       socialnetworkingsites
interface operation whereas Complete traceability is observed                     TABLE I: The 13 SMAs evaluated,the app stores they belong
in about 19% of the cases. We also report our experiences                         to, number of reviews and downloads when available.
using the methodology, together with lessons learned and                                        SMA             Platform      No. of         Installs
                                                                                                                              Reviews
potential future improvements to the methodology.                                               iSocial           Cydia          −              −
                                                                                              Hootsuite        Google Play     80760      1000k - 5000k
                          II. M ETHODOLOGY                                                      Buffer         Google Play     24948       500k - 1000k
                                                                                          Social Networking    Google Play     18336      1000k - 5000k
   We begin by listing the various SMAs we have considered                                    all in one
                                                                                            Social Media       Google Play     11106      1000k - 5000k
in our research along with their sources. We have surveyed 13                                 all in one
popular SMAs for this research. We studied the 6 most popular                                 Everypost        Google Play     4502        100k - 500k
                                                                                            Social Media       Google Play     1392        100k - 500k
SMAs (in terms of reviews and installs) each from Google                                      Hootsuite          iTunes        4865            −
Play Store and iTunes. Additionally, we included a Cydia                                        Buffer           iTunes        1150            −
                                                                                              Everypost          iTunes        138             −
SMA to account for the variation between SMAs with different                              Social Media Vault     iTunes         12             −
levels of adoption as well as between different app stores that                              Social butter       iTunes        N/A             −
                                                                                              Social hub         iTunes        N/A             −
have different vetting procedures or policies (e.g., Cydia only
works on rooted iOS devices and does not have a vetting
process in place). The SMAs are listed with their platform,
number of times they have been rated and the number of times
they have been downloaded (wherever available)4 in Table
I. Note that number of reviews was not available for Social
Butter and Social hub as there were not enough reviews for
iTunes to publish the number.

A. Examining Data Permissions
   The first step of our analysis requires us to identify exactly
which SMAs request permissions to access personal data
from the user. All mobile applications are required to request
permission for the data they access on the user’s phone. We
compare the permissions requested by the 11 SMAs included
in our analysis. It is important to note here that applications                   Fig. 1: Mobile data access permissions required by Hootsuites
asking for permissions of any data from the user does not                         on Android device
mean they are actually accessing it. However, it means that
this data is available to them with the consent of the user
(demonstrated by granting the access permission while using                       SMA had been granted. The permissions can also be checked
the application).                                                                 by the user when the SMA is used to log in to a particular
   Most applications have a “permissions screen” which is                         social network account for the first time. Only permissions
shown to the user to communicate the list of data access                          which were specified explicitly in either the permission screen
permissions requested by the application (refer to Fig. 1).                       or the phone settings (or seen using “Permissions Manager”
However, for the analysis, in addition to the permissions                         on Android SMAs) were included in our results.
screens, we also looked at the phone settings section for
the individual permissions the applications were using. Both                      B. Privacy Policies
Android and iOS display the data access permissions for                              The next step in our analysis was to examine the privacy
each application installed on the mobile phone. We also                           policies of the individual SMAs. In some cases, the relevant
checked the permissions granted to individual SMAs by using                       document was titled differently (such as “Terms of Service”)
“Permissions Manager” application on Android devices. We                          but we refer to all privacy related documentation as privacy
examine the social network data (such as profile information,                     policies for simplicity. The aim of this evaluation was to check
communication, lists, etc.) that are accessed by the SMAs                         for compliance with distributor vetting policies.
separately. This helps us understand exactly what information                        The 3 app stores included in our research are:
each SMA will try to have access for each of the SNS the user                       1) Cydia: It does not have an official vetting process for its
will associate to the SMA. To look at this, we created social                          applications.
media accounts and then authorized the individual SMAs. We                          2) iTunes Store: It has a vetting process which reviews all
then checked the social media site to see what permissions the                         applications.5 Personally identifiable information may not
                                                                                       be collected or used without the user’s consent. More
   4 These figures were found from the respective app stores and are accurate
                                                                                       generally, privacy policies are required if an application
as of 9th February, 2017. Please note that Apple does not publish official
statistics about number of downloads for individual iOS applications so this           stores, shares or uses personal data.
information is absent from the table. Statistics for iSocial could not be found
as well.                                                                            5 https://developer.apple.com/app-store/review/guidelines/
  3) Google Play Store: It has a vetting process which looks             policy, to that presented through application operations. Trace-
     at app permissions6 and outlines the application provider           ability between data actions and the extent to which we control
     agreement to protect the privacy and legal rights of                each privacy implication is the second aspect for analysis. In
     users.7 If an application accesses registration or personal         this way we map privacy implications to data transparency and
     information, users must be made aware of this, and an               control operations for SMA applications with privacy policies,
     adequate privacy policy must be provided in appliance               by carrying out the following steps.
     with the law.                                                          For each privacy implication identified:
C. Mapping Traceability                                                    1) Identify a corresponding interface operation by matching
                                                                               terminology of data actions.
   Finally, we performed a qualitative analysis of the privacy
                                                                           2) Assess the transparency of data actions made visible to
related documentation to facilitate the traceability analysis
                                                                               the user through interface operations, contrasting data
with transparency and control interface operations. Previous
                                                                               actions in privacy policies.
research has identified a methodology for analysing software
                                                                           3) Assess the extent of user control on data actions through
requirements from privacy policies [1]. Concepts, catego-
                                                                               operations, mapping data visible in the previous step (2)
rized as a commitment, privilege or right, are attained from
                                                                               with control operations.
statements by identifying helping verbs, and used to produce
a set of software requirements. Similarly, we use content                   We measure the extent to which privacy implications are
analysis to identify action statements through verbs that we             transparent and controllable through user interfaces against
then categorize into privacy implications, which are split into          three main categories; complete, partial and broken in a
categories by way of answering the following questions:                  similar way as in Anthonysamy, et al. [2], but specifying
                                                                         the categories both for transparency and control:
  1) What information is collected by the application?
                                                                            Complete mappings signify complete transparency of infor-
  2) What is the purpose of collection?
                                                                         mation presented to the user, through both transparency and
  3) Who can access this information?
                                                                         control operations. Information presented to users is unam-
  4) How long is information retained?
                                                                         biguous; with unmistakable meaning and appropriate detail.
   These privacy implications help us in contextualizing the
                                                                         For transparency, complete traceability can be achieved by
traceability analysis. In particular, we map the extent to which
                                                                         providing accurate information to the user through the user
application features and controls match expectations set out
                                                                         interface. An example is when a user is accurately informed
to users as data actions in privacy policies or application
                                                                         about all data being accessed by an app through the permission
interfaces. By measuring the traceability of privacy policy
                                                                         screen. The control operation is mapped as complete when the
implications in application content, we can assess the extent
                                                                         user can regulate this list and can choose to withhold certain
to which data transparency and control are delivered to the
                                                                         items of information.
user.
                                                                            Partial mappings involve ambiguous information provided
   For those applications with privacy policies, information
                                                                         in privacy documentation or data operations. For example,
provided in these documents present a means of gathering ex-
                                                                         vague terms like ‘personal information’, which are not explic-
pectations for this analysis. A method for traceability analysis
                                                                         itly defined, make mapping data operations difficult. Access
of SNS is presented by Anthonysamy, et al. [2] where action
                                                                         permissions are partial data operations because they do not
statements identified in privacy policies are mapped to those in
                                                                         inform users of all data collected. Hootsuite collects location
interface operations by way of assessing the extent to which
                                                                         and traffic data, much like most other applications. Although
data actions are controllable by users. We applied a similar
                                                                         we are prompted for permission regarding location access,
methodology to SMAs and extended it to consider mobile
                                                                         the application does not provide any information on the user
phone data and the transparency of interface operations. In
                                                                         of traffic data collection. Control over a privacy implication
Anthonysamy’s methodology, privacy implications found in
                                                                         is found to be partial when incomplete, with some control
policies are matched to corresponding operations available
                                                                         provided but not all data collected have associated controls.
through interfaces during installation and use of the applica-
                                                                         Taking Everypost as another example, we find partial control
tion. We have defined actions of privacy policies as privacy
                                                                         operations are evident for traffic data collected. Everypost’s
implications, and define features and controls of an application
                                                                         privacy policy8 states that cookies used by third parties may
as its operations. Also, and extending upon Anthonysamy’s
                                                                         be opted out of, as is apparent through interface operations.
methodology, our study aims to identify the traceability of data
                                                                         However, collection of traffic data for internal usage such as
privacy implications through interface awareness mechanisms.
                                                                         analytics does not match any control operations.
Therefore we assess the transparency of data actions through
                                                                            Broken mappings occur when there is a disconnect between
interface operations, as well as controls.
                                                                         privacy implication expectations and application operations.
   For SMAs with privacy policies, transparency of data usage
                                                                         Control operation mappings are broken when documented
is analyzed, mapping information provided in the privacy
                                                                         expectancies and/or data transparency operations do not have
 6 https://support.google.com/googleplay/answer/6014972?hl=en-           a matching control. Detachment from policy expectations is
GB&ref topic=6046245
 7 https://play.google.com/about/developer-distribution-agreement.html     8 http://everypost.me/privacy-policy/
                                                  TABLE II: Mobile data accessed by each SMA
        SMA            Identity   Photos   Location   Contacts   Wi-Fi   Camera    Mic   Device ID     SMS   Phone   Network    In App      USB
                                  /Media                                                 & Call info                  Access   Purchases   Storage
        iSocial           3         −         −          −        −        −        −        −          −     −         3          −          −
      Hootsuite           3         3         3          −        3        −        −        −          −     −         3          3          3
        Buffer            3         3         −          −        −        3        −        −          −     −         3          3          3
  Social Networking       −         −         3          −        3        −        −        −          −     −         3          −          −
      all in one
    Social Media          −         3         3          3        3        3        3        3         3      3        3          −          3
      all in one
      Everypost           3         3         3          3        3        −        −        −          −     −        3          3          −
    Social Media          −         −         3          −        −        −        −        −          −     −        3          −          −
      Hootsuite           3         3         3          −        3        −        −        −          −     −        3          3          3
        Buffer            3         3         −          −        −        3        −        −          −     −        3          3          3
      Everypost           3         3         3          3        3        −        −        −          −     −        3          3          −
  Social Media Vault      −         −         3          −        −        3        −        −          −     −        3          −          −
     Social butter        −         3         3          −        −        3        −        −          −     −        3          −          −
      Social hub          −         3         3          3        −        −        −        3          −     3        3          −          −

 Key:         Yes: 3      No: −



apparent among privacy implications such as advertising and                    permissions requested by SMAs while a user logs into their
aggregation. These purposes for data collection are expressed                  social media accounts in Table III. We have used general terms
in privacy policies but no corresponding information is pro-                   such as “Activity” and “Lists” in this table to simply convey
vided through application data or control operations. Likewise                 the meaning as each social media site uses different names for
implications of age restriction in concern to data retention are               such features. For example, “posts” on Facebook and “tweets”
expressed in policies with disconnect to interface operations.                 on Twitter as well as inbox messages are classified under
   There are many cases in which there is an absence of a                      “Activity”. Similarly, “Lists” refers to groups or lists that the
clear traceability mapping between privacy implications and                    user might have created (or used by default) to organize their
interface operations. We have classified these applications as                 contacts on various social media sites.
Unknown and represented them in our analysis.                                     We can find in Table III that 5 SMAs, namely, iSocial,
   Apart from the above 4 classifications, there are some                      Social Networking All in One, Social Media all in one, Social
cases where the privacy implication was not applicable to a                    Media and Social Media Vault are marked with a ‘ * ’
particular SMA. In such cases, we have represented this as                     sign and are shown to access all social media data. This is
N/A in our analysis. The detailed results of our analysis is                   to highlight the fact that these applications do not disclose
presented in section 4.3.                                                      what social media data they access to function as they just
                                                                               provide an interface for either the social media apps (such as
                              III. R ESULTS                                    Facebook, Twitter) already installed on the user’s phone or
A. Data Access Permissions                                                     to the web link of the social network via the web browser.
   1) Mobile Data Access Permissions: As can be seen from                      As all the social media activity goes via these applications,
the results in Table II, most applications require access to                   they have the potential to access all communication. Moreover,
photos/media, location, identity, which refers to any user ac-                 these applications do not require to be authorized by the
counts on the phone accessed by the application, and network                   user with their Facebook account so the user cannot regulate
access. In addition, many application require access to the                    the permissions by logging into their Facebook account as
USB storage as well. These findings confirm that personal data                 is possible with other Facebook applications. For the other
of the user is accessed by most of the application that were                   SMAs, we find that many of them access almost all social
analyzed. An interesting observation is that permissions seem                  media activity such as posting on walls/tweeting, access the
consistent for the same SMA developers across app stores.                      friend or contact lists, update the profile on the users’ behalf,
However, for different SMAs we observe a wide variety in                       post on their behalf, access to inbox messages or the email
the mobile data being accessed. While this could be attributed                 ID which was used to create the account. Needless to say, all
to different functionality being provided, it may also be a sign               this information may be classified as personal and sensitive to
of some SMAs asking for more permissions than required [3],                    the user and we find that most applications who disclose the
as arguably one of the most mature and used SMA (Hootsuite)                    permissions access this information.
seems to use a relatively smaller set of permissions when
compared to other SMAs. An interesting case is that of Social                  B. Application Privacy Policies
Media all in one, which seems to access everything except                         Applications that collect personally identifiable information
Identity (which could be retrieved from the SNSs accessed                      are required to produce a privacy policy in order to comply
anyway).                                                                       with the previously discussed distributor vetting policies. Table
   2) Social Media Data Access Permissions: SMAs are dif-                      IV shows that 8 out of the 13 SMAs that we evaluated were
ferent from other mobile applications as they can access a                     found to include this documentation. The lack of privacy
user’s social media data as well. We have summarized the data                  policies among the other 5 SMAs seems to suggest a vio-
   TABLE III: Social media data accessed by each SMA                          TABLE IV: Whether privacy policies are provided by each
        SMA            Activity   Lists   Update    Post   Messages   Email   SMA provider
                                          Profile                      ID
                                                                                                            SMA                                  Privacy Policies
       iSocial*           3        3        3        3        3        3
      Hootsuite           3        3        3        3        3        3                                   iSocial                                      3
        Buffer            3        3        3        3        3        3                                 Hootsuite                                      3
 Social Networking*       3        3        3        3        3        3                                   Buffer                                       3
       all in one                                                                               Social Networking all in one                            −
   Social Media*          3        3        3        3        3        3                          Social Media all in one                               −
       all in one                                                                                        Everypost                                      3
      Everypost           −        3        −        3        −        3                                Social Media                                    −
   Social Media*          3        3        3        3        3        3                                 Hootsuite                                      3
      Hootsuite           3        3        3        3        3        3                                   Buffer                                       3
        Buffer            3        3        3        3        3        3                                 Everypost                                      3
      Everypost           −        3        −        3        −        3                             Social Media Vault                                 −
 Social Media Vault*      −        3        −        −        −        3                                Social butter                                   −
    Social butter         −        3        −        −        −        3                                 Social hub                                     3
      Social hub          3        −        −        −        −        3
                                                                                                Key:            Yes: 3                No: −
 Key:       Yes: 3       No: −

                                                                              TABLE V: Traceability mappings represent transparency and
                                                                              control of privacy implications respectively, or collectively.
lation of the distributor vetting policies which mandate such
documentation for all applications which process personal data




                                                                                                            Social hub


                                                                                                                         Hootsuite


                                                                                                                                     Hootsuite


                                                                                                                                                  Buffer


                                                                                                                                                              Buffer


                                                                                                                                                                        Everypost


                                                                                                                                                                                    Everypost

                                                                                                                                                                                                iSocial
from users. We did find in Table II that the SMAs without
a privacy policy do not access “Identity”, so technically
                                                                                       Collection
they may argue they do not access personally identifying                             Mobile Data            G#            G#         G#            G#         G#        G#          G#
information. However, they are found to be able to access                         Social Media Data          G#           G#           G#          −           −        G#           G#          l
most of the social media data, photos, location, etc., which                          Traffic Data            6           6           G#           6           6        G#           G#          6
                                                                                        Purpose
can be classified as personal information.                                              Services             6   G#
                                                                                      Internal use            6          G#           G#           6           6        6            6           6
                                                                                     Asset transfer           ?           6           6             ?           ?       6            6           6
C. Traceability for Transparency and Control                                          Advertising           G#           6G
                                                                                                                          #           −            −           −        −           6   G#       6
                                                                                     Aggregation              6           6           6            6           6        −            −           ?
   Common data actions have been categorized to form 14                                  Access
privacy implications seen in the left column of Table V.                           Service Provider         G# G# G# G# G# G#                                                       G#           6
                                                                                  3rd party by user          G#   6 6   6  6
Privacy implications fall under further categories by way                       3rd party by provider        6G# 6 6   −  −  ?                                                       ?           6
                                                                                        Legality              6           6           6            6           6        6            6           6
of answering our privacy questions set out in section 3.3;                             Retention
collection, purpose, access and retention of data. Operations                       Age Restriction          G#           6           6            6           6        6            6           6
                                                                                      Information             6           6           6            −           −        6            6           −
refer to features provided by SMA providers or distributors                    Key:
which inform us of data collection and use as well as pro-                     Complete:                   G#
                                                                                                    Partial:             Broken: 6                         Unknown: ?               N/A: −
viding us with control over data actions. Each symbol in
the table provides a mapping to the degree of traceability
offered by transparency and control operations respectively.                  terms and conditions specifies privacy implications; “Any site
Data operations refer to the extent to which transparency of                  registration information is used only by the website and is
data actions is presented to the user through interfaces, these               not sold or given out to others”, likewise users may provide
include access permission prompts and other mechanisms                        an email address for the service provider to provide support.
which detail privacy implications. Control operations refer to                Complete transparency for collection can be found when an
features and mechanisms presented through interfaces which                    SMA communicates the data its going to access to the user
enable control over some data action, these include device                    through the interface operations. Fig 2a shows Hootsuite’s
settings, accept/decline button options etc. If the same degree               permissions screen which tells the user about the social media
is found for both transparency and control operations assessed,               data that will be accessed by it. Complete traceability mapping
then only one symbol need be provided in representation. If                   for control operations are when a user can regulate the access
a different degree of traceability is found, the first symbol in              permissions through interface operations (such as Fig. 2b
the particular cell of the table corresponds to transparency                  which shows Hootsuite for iOS).
operations and the second symbol corresponds to control                          Users have control over content provided for use by ser-
operations. In the resulting table, we refer to content as the                vices, through accepting access permissions and the posting
social media data collected shown in Table III. Other privacy                 of information. Sharing information intentionally with SNS
implications and results will be further explained and justified              involves sharing this with these third parties by users, the
in the following subsections.                                                 transparency of third party access is completely apparent to the
   1) Complete: All SMAs provide control over some data                       user in this case. Some applications offer settings which enable
collection through access permissions. iSocial does not specify               the user a level of control over who accesses information
any such method of informing the user of data collected                       posted to SNS, and the restriction of data access to particular
through the requirement to accept access permissions. iSocial’s               accounts. Controls offered are as found on common SNS;
                                                                    TABLE VI: Summary of traceability mappings for trans-
                                                                    parency, control and overall traceability of all privacy implica-
                                                                    tions analyzed. Figures rounded to the nearest whole number.
                                                                                           Complete   Partial   Broken   Unknown   N/A
                                                                                 Transp.     29%        0%       57%       7%       7%
                                                                       Cydia     Control     29%        0%       57%       7%       7%
                                                                                  Total      29%        0%       57%       7%       7%
                                                                                 Transp.     17%       24%       43%       2%      14%
                                                                      Android    Control     17%       19%       45%       5%      14%
                                                                                  Total      17%       21%       44%       4%      14%
                                                                                 Transp.     14%       27%       45%       4%      11%
                                                                       iOS       Control     22%       17%       45%       5%      11%
                                                                                  Total      18%       22%       45%       4%      11%
                                                                                 Transp.     17%       23%       45%       4%      12%
                                                                      Overall    Control     21%       16%       46%       5%      12%
                                                                                  Total      19%       19%       45%       4%      12%


                                                                    likely to use and share traffic or aggregate data with third
(a) Notification of Social Me-    (b) iOS device settings which     parties, for the purpose of analytics and advertising. We are
dia data access by Hootsuite      enable users to restrict access   unable to determine whether an application without a privacy
                                  permissions                       policy passively collects such non-identifiable information.
         Fig. 2: Transparency and control operations                Therefore, for some SMAs, data disclosure to 3rd parties by
                                                                    the provider are shown to be unknown.
                                                                       5) Summary: Table VI summarizes our results, presenting
share with only friends or everyone. Asset transfer refers          rounded percentages of privacy implications found to be com-
to personally identifiable information being transferred as         plete, partial, broken, unknown or not applicable. We provide a
businesses buy and sell assets.                                     breakdown for each of the 3 app stores. The overall traceability
   2) Partial: The transparency of privacy implications             of transparency and control are also provided.
through access permissions maps only partially to expectations         We find a general lack of transparency across SMAs with
provided by SMA privacy policies. An example of which               45 percent of SMAs revealing broken transparency mappings.
is partial content collection made visible and controllable to      Privacy implications offering complete transparency of data
the user. SMAs with privacy policies commonly state their           involve collection of personal information made visible to the
rights to collect all information provided to the site, including   user through in some way (e.g. showing the access permis-
shared with associated SNS. Google Play’s Hootsuite provides        sions required). In order to consider current guidelines for
a ‘Send usage data’ setting; the user is informed anonymous         user privacy as adequate, we must rule out mistrust between
data is collected which is used to help improve Hootsuite.          the user’s expectations and reality of how SMAs treat their
Partial transparency and control over internal use is apparent,     information by making them aware, either through privacy
with an ambiguous description collection and purpose, along         policies or through other awareness mechanisms, of any data
with control over ‘anonymous data’ but no matching control          collected, how it will be used, whom it will be shared with,
for all data collected as specified in the privacy policy, such     and how long it will be retained.
as content posted.                                                     We also find that users have a lack of control as less
   3) Broken: Internal use of data includes analytics used          than a quarter of the results indicated complete control over
to improve or better understand services. It is common for          privacy implications. In order to give more control to users,
servers to automatically collect usage information; “Server         developers could work to increase application functionality
logs may include such information as a mobile device identi-        while restricting access to data. Settings should enable control
fication number and device identifier, web requests, IP ad-         over all data collected, including information perceived as non-
dress, browser type, browser language, referring/exit pages         identifiable. Research has shown that pragmatic approaches of
and URLs, platform type, number of clicks, domain names,            providing privacy related intervention, where users are shown
search terms, landing pages ...”, the list goes on and on. This     the effect of exposures of their data, work well [4].
type of information collected is referred to as the traffic data
privacy implication, and may be shared with third parties on                    IV. D ISCUSSION AND L ESSONS L EARNED
an aggregate basis for advertising and analytic purposes. We           In this paper, we inspected how SMAs handle privacy
can see that both transparency and control for this example are     and looked at it from three different angles. Evaluating the
broken in most SMAs, leaving users unaware in their normal          permissions requested by the SMAs was fairly straightforward.
use through the interface of the collection of this data and        The SMAs communicate permissions to the user directly
without a way of controlling that in any shape or form.             and the user also has the opportunity to verify social media
   4) Unknown: Analyzed traceability mapping of data use            permissions by checking their social media account and autho-
as specified in privacy policies has shown us not to expect         rizing the applications. While there are many tools that enable
applications to inform users about the passive collection of        the user to automatically check the mobile data permissions
non-identifiable information. We are aware that providers are       requested by apps, checking of social media permissions
is slightly more complex. The process may potentially be           researchers to conduct the traceability analysis and look for
automated by simulating an authorization of the SMA to a           a consensus based approach or provide inter-rater reliability
dummy social media account (like a “guest” account, possibly       between multiple researchers. This would potentially enhance
built-in to the SMA), to reveal the permissions to the user,       the objectivity of the traceability analysis.
before they use the SMA with their own social media account.
The larger problem here seems to be the lack of understanding                            V. R ELATED W ORK
that users have about the permissions requested by mobile          A. Analysis of Mobile Data Access Permissions
applications. Greater awareness is desirable where users are          Mobile applications generally are explicit in disclosing the
informed about the implications of the permissions they are        data access permissions they require to the users. There is
granting.                                                          generally a screen which is shown to the user at the time
   While looking for privacy related documentation, we found       of installation which tells them the data that the particular
a fair degree of ambiguity. Not only do different application      application will be allowed to access. The major issue is the
providers have different names for such documentation (“pri-       “all or nothing” nature of mobile applications [6]. The user is
vacy policy”, “terms of service”, etc.), there is an absence of    required to grant the requested permissions to the application
consistency in the content of these documents as well. This        for them to use it. This is a problem as it has been shown that
inconsistency makes it difficult to construct any expectations     mobile applications often introduce risk vectors by asking for
from the users’ perspective of what they should be looking for     more permissions than required [3]. The problem is that the
in order to educate themselves about the privacy implications      applications are somewhat hamstrung in this regard and have
of using a particular app. Moreover, we found 5 SMAs which         to request for permissions that they envisage using at any time
do not provide this documentation at all. This is, as pointed      during execution. There have been some solutions put forth
out earlier, in clear disagreement with the vetting policies of    to detect and possibly prevent malicious mobile applications
both Google Play and iTunes app stores. A possible mitigation      by using anomaly detection to detect applications behaving
may be found in automated solutions like “AutoPPG” which is        maliciously and in a deviant manner from normally expected
an automatic privacy policy generator for Android applications     behavior [7]. The idea is to use static analysis to create profiles
[5]. It simply identifies the important privacy issues emanating   of applications’ expected behavior and detect anomalies at run-
from the usage of the application by conducting a static           time to secure mobile applications. This is similar to the work
analysis of the application’s source code. Automated solutions     of Hussain et al. which looks at detecting malicious database
such as these may enable development of a consistent structure     applications [8]. Another proposed approach, “PrivacyGuard”
and terminology in such privacy policies which would enable        uses the VPN service of Android devices to intercept network
easier traceability analysis. Furthermore, such mechanisms         traffic of mobile applications to detect information leakage
may also encourage SMA and other application developers            [9]. It also provides mechanisms of tricking the malicious
to include privacy policies without putting in too much effort.    applications by manipulating the leaked information. We found
   The qualitative analysis of privacy policies and analyzing      that most of the previous work in this area only looks at
traceability with interface controls was a comparatively less      leakage of mobile data and not social media data which SMAs
objective part of our methodology. Such analysis is harder due     have access to as well.
to the relative inconsistencies in privacy related documentation
across apps as mentioned earlier. Moreover, the interfaces         B. Analysis of Privacy Policy Traceability
for each individual SMAs have different operations which              There is previous work which shows that control over
necessitate a case-by-case analysis. This is the most costly       data disclosure can affect decisions made by users [10].
part of the methodology in terms of time and effort. It is         Greater transparency about data being shared often acts as a
possible to automate the traceability analysis if the privacy      mitigating factor against erroneous decisions being made. Our
documentation is standardized and the privacy implications are     work looks at the traceability for transparency and control by
clearly defined. It is an interesting future direction in which    looking at the interface operations and how closely they match
research can progress where such an automatic tracaeability        with privacy policies. Qualitative analysis of documented
analysis might be used to certify SMAs. Any such efforts can       policies and analyzing traceability with interface features is
rely on the analysis methodology shown by similar work in          an extensively researched topic in software engineering. More
the area of social media sites and indeed the work done in this    recently, this technique has been used to analyze whether
paper.                                                             the privacy policies outlined by SNSs are congruent with
   The methodology proposed in this paper may also be              the interface controls provided to the users. Anthonysamy et
extended to other apps which provide users with the oppor-         al. demonstrated that SNSs themselves suffer from a lack of
tunity to link their social media accounts (such as gaming         traceability between data actions defined in privacy policies
apps). It would be interesting to see whether the problems         and corresponding data operations apparent to users through
highlighted in this paper are specific to SMAs or whether          interfaces [2], [11]. Our work extends this methodology
other similar apps, which let the users post to multiple social    to perform a privacy analysis for SMAs by performing an
media accounts, portray similarly low traceability. Future at-     analysis of the mobile phone data and social media data
tempts at using this methodology may consider using multiple       accessed by the SMAs in addition to a traceability mapping
which considers the transparency of interface operations and                    [11] P. Anthonysamy, P. Greenwood, and A. Rashid, “A method for analysing
the control provided to the user.                                                    traceability between privacy policies and privacy controls of online
                                                                                     social networks,” in Privacy Technologies and Policy. Springer, 2014,
                                                                                     pp. 187–202.
                         VI. C ONCLUSIONS
   In this paper, we described a three-step methodology to
examine the privacy issues posed by SMAs by examining the
data (both mobile and social media) permissions requested
by them, checking whether they provide the user with pri-
vacy related documentation and analyzing traceability between
privacy implications identified in the privacy policy with
the interface operations provided to the user. We used this
methodology to evaluate 13 popular Social Media Aggregators
(SMAs) from 3 app stores and found that the majority of
the SMAs we evaluated accessed users’ personal information
including their social media activity. However, we also found
that 5 of the 13 SMAs did not provide any privacy related
documentation which is in clear conflict with the vetting
policies of the app stores. Our results show that 45% of SMAs
show Broken traceability between privacy documentation and
interface operations while Complete traceability is observed
in only 19% of the cases. These results highlight the need for
major improvements to ensure that the usage of SMAs does
not compromise user privacy. The methodology described in
this paper can be reused for further investigation of SMAs or
be extended, with certain improvements, to examine similar
applications which enable the user to link their social media
activity.
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