How can social networks access your contacts in email?
 

Dutch article on a popular social network


Translated:

In a study by University of Cambridge, Badoo scored lowest in a study comparing 45 social networks.
If someone joins Badoo, (s)he can count on it that private contacts from an email account of Facebook account will be notified/kept updated on this membership (of Badoo). Badoo even searches for contacts on other email accounts and Facebook accounts of its members. This probably occurs via similar passwords.



I realise that Wikipedia is not Always true, and in the English language page there are other criticisms but none going as far as contacts from an email account or Facebook account being notified of one's membership.


Is it really possible that upon joining a social network, the social network (doesn't matter which) can access one's email account in order to send invites to all contacts in that email account used for signing up? I mean, unless one is clumsy enough to use identical passwords, the social network for which one signs up may know the email address used to sign up by the new member, but the social network doesn't have the actual password of that email account. So how is it possible that they'd send invites and thus know which contacts are in that email account? That'd require actually logging in to the email account used to sign up, which should be impossible without knowing that email account's password. :confused:

Most people sign up using their smartphone and when they do there is usually a screen asking for all sorts of permissions. Everyone ignores the messages on that screen and accepts the permissions, giving the app instant access to your contacts and often your camera, your location, and a bunch of other stuff that seems irrelevant to the app's function. Technically, app producers are supposed to be limited in what they use all the permissions for, but there have been many reported instances of privacy issues. There are also APIs that companies make to allow app producers to access your contact information on desktop, etc. For example, I have purchased a program before that would allow access to migrate my Google Contacts and Emails to another provider--trusting that they wouldn't be stealing the information, but again, who knew?

But is it technically possible that a website, when not using an app on a smartphone but simply signing up through a browser on desktop, can access your email account or Facebook account in order to send invites to your contacts? I mean, doesn't that require access into your email account and Facebook, and thus having to know your password?

I'm struggling to understand whether (and how) this is possible at all, but the Wikipedia article I refered to isn't reassuring at all… Makes me want to reconsider joining those social networks in the first place. I don't mind a site knowing my location, browser type, etc (I don't know why they need that info, but hey, go ahead and ask) but I don't want outsiders to access my email accounts... Both for the sake of privacy and for the sake of not wanting my friends to receive spam sent through some site I chose to join.

True about most people.

I on the other hand am very selective on what Apps can access my Contacts. Thankfully most Apps do not make this the default and ask permission. Even the Facebook App does not access Contacts unless you allow it.

With my Samsung S7 edge, it fairly simple to control which Apps get what permissions. I currently allow 5 of 78 apps access to Contacts, two of those are Contacts and Secure Folder Contacts.

I generally when installing a new App verify what permissions it has and turn off those I feel are not needed. That App if it does need it will let me know, then I will decide if it that permission or I remove the App.

I cannot see how any social network could access one's email account, as long as that account is not part of that service. Take Google (one access for services) for example. The soon to be shutdown Google+ could gain conceivably gain access to your Gmail Contact list. That said, I do not see any sort of connection between my Google+ and Google Contacts. I don't have any contacts in Google Contacts, but I don't think that is why. I just can't find any connection to Google Contacts from Google+

I do all email from a client (Claws Mail) on this computer, the Gmail App on my cell phone does not have access to my cell phone Contacts.

All of my web base email accounts have similar empty contacts list for the same reason, any App install for that service is denied access to Contact on the cell phone.

My cell phone contacts are quite different than my email contacts.

I site that allows access via a social network service like Facebook or Google

From that Dutch Wkipedia page at the bottom (translated)
Is not sourced, I don't see how this citation is possible as stated. Badoo does have a sign up option via Facebook though so I would presume that would give them access to Facebooks Friends list. As for other email, just can't see that happening. Badoo would need the password. I'm not about to sign up for Badoo to test this. :D