Sex, Lies, or Kittens?
Investigating the Use of Snapchat’s
Self-Destructing Messages
Franziska Roesner1, Brian T. Gill2, Tadayoshi Kohno1
1 University
of Washington, Computer Science & Engineering
2 Seattle Pacific University, Mathematics
Snapchat: Disappearing Messages
As of late 2013:
- 350 million “snaps” per day.
- Estimated over 30 million active users.
- Attempted purchase by Facebook: $3B.
Official Snapchat screenshots (https://play.google.com/store/apps/details?id=com.snapchat.android).
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Snapchat: The Sexting App?
Research Question: How and for
what do people really use Snapchat?
http://dacoolcat.tumblr.com
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Snapchat: Not Actually Secure!
Snapchat messages can be saved…
(1) Via screenshots (sometimes secretly).
Research
Questions:
(2) Retrieval
after deletion.
- What are user’s screenshot
practices and reactions?
- Do people trust Snapchat, and
does that affect use?
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Our Research Questions
1. Usage Patterns: How and for what do
people really use Snapchat?
2. Screenshot Practices: What are users’
screenshot practices and reactions?
3. Effect of Security Weaknesses: Do people
trust Snapchat, and does that affect use?
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Outline
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Background and Motivation
User Survey Results
Implications
Summary
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Outline
•
•
•
•
Background and Motivation
User Survey Results
Implications
Summary
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User Survey
127 adult Snapchat users.
(206 initial participants: 18 screened out for not knowing
Snapchat, 61 for not using it.)
Recruited via social media + university email lists.
Up to 41 questions, 15-30 minutes.
Limitations: adults, snowball sampling (high security
expertise), multiple choice, possible under-reporting.
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Demographics (1/2)
68.5% male, 29.9% female.
Skewed towards younger adults:
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81.9% age 18-24
14.2% age 25-34
1.6% age 35-44
0% age 45-54
1.6% age 55-64
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Demographics (2/2)
Skewed towards higher security expertise
(but no detected effect on most responses).
5% Novice --- 17% --- 29% --- 31% --- 13% Expert
Westin Privacy Index:
– 39% Privacy Fundamentalists
– 46% Privacy Pragmatists
– 13% Privacy Unconcerned
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Our Research Questions
1. Usage Patterns: How and for what do
people really use Snapchat?
2. Screenshot Practices: What are users’
screenshot practices and reactions?
3. Effect of Security Weaknesses: Do people
trust Snapchat, and does that affect use?
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(1) Usage Patterns
Do respondents send sensitive content?
Does message timeout behavior reflect privacy
considerations?
Do respondents use Snapchat for security
and/or privacy reasons?
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Sensitive Content?
Sending sensitive content is
uncommon, though up to
25% may do so
experimentally.
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Useful for Non-Sensitive Content
“It lets me have more cats in my life because my
friends who don’t normally post pictures of their cats
on other social media will snapchat their cats to me.”
“The fun of it is you can send a stupid face
or a snapshot of what’s happening. The
communication is compact and fast.”
“There should be an option to recognize
faces and add moustaches to those faces.”
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Message Timeout Behavior
47.2% change timeout based on content/recipient.
Shorter timeouts:
– 22.8% for embarrassing photos.
– 10.0% for secret information.
– 10.0% for less trusted recipients.
Longer timeouts:
– 18.9% for more trusted recipients.
– 9.4% (write-in) for complex content.
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Why Snapchat?
46.5% use it because content is unlikely to be saved.
Not necessarily for privacy reasons!
“Expectation of spam means it’s okay to spam.”
“Some content, whether or not it’s risque, does not
need to be seen more than once (e.g., photos of food).”
66.1% use it because it’s simple, 55.9% because it’s fun.
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(2) Screenshot Practices
How often do respondents
take screenshots?
How do respondents and
their contacts react to
screenshots?
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Screenshot Behavior
Screenshots are common: 47.2% report taking
screenshots, 52.8% have had them taken.
(3.9% have used a separate camera.)
Most respondents don’t intend to violate trust,
but 10.2% say they have taken a screenshot to
embarrass the sender.
“We have a tacit agreement that if the timeout
is 10sec, then a screenshot is almost expected.”
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Screenshot Reactions
Screenshots are not
usually a trust violation.
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(3) Effect of Security Weaknesses
Do respondents know that Snapchat message
destruction is insecure?
Do respondents report security-related
behavior changes?
Does lack of trust in Snapchat affect content
respondents send?
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Understanding (In)Security
A majority of respondents understands that
Snapchat is not secure: 79.5% know or suspect
that recovering messages is possible.
Only 14.1% “know” or think that message
recovery is impossible.
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Reported Behavior Changes
52.8% would not change their behavior in
response to learning that Snapchat is insecure.
38.6% would change / have changed behavior:
– 24.4% would use it differently.
– 14.2% would use it less.
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Observed Behavior Changes
A majority of respondents is unwilling to send certain
types of content via Snapchat: sexual, documents,
legally questionable, mean/offensive/insulting.
Why?
Most because they “never take pictures of that sort
of thing” (30.7 – 73.2%).
The rest are concerned about Snapchat insecurity (up
to 14.2%) and screenshots (up to 25.2%).
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Outline
•
•
•
•
Background and Motivation
User Survey Results
Implications
Summary
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Implications for Snapchat
Misconception #1: Primarily for sensitive content.
Snapchat “has a bad
reputation (for sexting).”
“It seems useful only for
inappropriate content.”
Misconception #2: Success
threatened by vulnerabilities.
Suggests: Snapchat should
(and does) market itself
differently.
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Implications for Secure Messaging
A sizable fraction of respondents reported
security-related behavior modifications.
“I like the idea of Snapchat, but it definitely
worries me that the photos are ‘out there’
somewhere, even if the snaps I’m sending
don’t have sensitive content.”
Suggests: Many users would still benefit from
a more secure messaging application.
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Open Questions
• How do teenagers use Snapchat?
• How much did respondents under-report
sensitive behaviors?
• How well do our survey results generalize to
a broader population?
Suggests: future, more behavioral studies of
Snapchat needed.
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Outline
•
•
•
•
Background and Motivation
User Survey Results
Implications
Summary
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Summary
Security and privacy in Snapchat
are not major concerns for the
majority of respondents.
Most understand that message
destruction is insecure.
But: many have/would adapt
behavior due to lack of trust or
security issues.
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