@shakedko
IF AN EXPERT SAYS IT CAN'T BE DONE GET ANOTHER EXPERT.
- DAVID BEN-GURION

Couchsurfing Privacy Issues

Description

Couchsurfing is one of the best products I have used in the last couple of years. It helped me to meet many people from all over the world, to host them or surf their couch and I am very thankful for that!

Privacy is an important thing. After exposing privacy issues with the Tinder app almost 2 years ago, I have started to doubt more and more different applications that require my personal information.

TL;DR

Couchsurfing allows people to see their users' private information such as:

  • User's Facebook profile URL - this means that with enough understanding people would be able to find Couchsurfing users on Facebook and contact them.
  • Emergency Contact Details - Although Couchsurfing promises that this information is only available for administrators, it exposes it to everyone. This means that if you fill up this form people would be able to see this information and use it (see screenshot bellow).

More information below.

Requirement

In order to follow this article you might need to know mitmproxy - installation instructions are available on my previous Tinder Privacy Issues post.

The Problems

User's Facebook Profile URL

The Couchsurfing app seems to expose the Facebook profile of users who logged-in with their Facebook accounts.

How

After installing mitmproxy and setting up all the above you will have to follow those steps:

  1. On your phone, open the target's profile.
  2. On your desktop, search for the following URL: https://hapi.couchsurfing.com/api/v2/users/{{user-id}}
  3. On the response tab look for facebookProfileUrl (see screenshot below).

Emergency Contact Details

On Couchsurfing's website a user can fill-in a form to write down who should be his emergency contact. On the form it says:

Emergency Contact information can ONLY be seen by administrators. It will be used if we need to get in touch with someone other than you in case of emergency. This could be a family member or close friend. Please include name, relation, phone number and email address.

It seems like this information can be seen by ANYONE.

How
  1. On your phone, open the target's profile.
  2. On your desktop, search for the following URL: https://hapi.couchsurfing.com/api/v2/users/{{user-id}}
  3. On the response tab look for emergencyContactInfo (see screenshots below).

Using the form from the picture above it will be possible to see the detail in the HTTP response:

Summary

I am not sure if Couchsurfing's privacy issues are critical as Tinder's but in my opinion those are problems that should be fixed as I wouldn't want people to find my Facebook profile and SPAM or annoy me. Having said that, I think that promising your users a safe service requires the company to put more cautious and be as responsible as it claims to be.

The above was tested using Couchsurfing for iOS version 3.4.

Timeline

  • May 20th - Sent an email mentioning the Facebook profile URL issue - No reply, was not fixed.
  • June 14th - Sent another email mentioning both issues.
  • June 29th - Didn't get any reply regarding those issues. Published new blog post.