Poultry Markets: On the Underground Economy of Twitter Followers
Twitter has become such an important medium that companies and celebrities use it extensively to reach their customers and their fans.
Nowadays, creating a large and engaged network of followers can determine the difference between succeeding and failing in marketing.
However, creating such a network requires time, especially when the party building it does not have an established reputation among the public.
For this reason, a number of websites to help Twitter users create a large network of followers have emerged. These websites promise their subscribers to provide followers in exchange for a fee. In addition, some of these services offer to spread promotional messages in the network.
We call this phenomenon Twitter Account Markets. We study this phenomenon in our paper "Poultry Markets: On the Underground Economy of Twitter Followers", that will appear at the SIGCOMM Workshop on Online Social Networks (WOSN) later this year.
Typically, the services offered by a Twitter Account Market are accessible through a webpage, similar to the one below. Customers can buy followers at a rate that is between $20 and $100 for 1,000 followers. In addition, markets typically offer the possibility of having content sent by a certain number of accounts, again in exchange for a fee.
All Twitter Account Markets we analyzed offer both "free" and "premium" versions of their services. While premium accounts pay for their services, the free ones gain followers by giving away their Twitter credentials (a clever way of phishing).
Once the market administrator gets the credentials for an account, he can follow other Twitter accounts (that are free or premium customers of the market), or send out "promoted" content (typically spam). For convenience, the market administrator typically authorizes an OAUTH application by using his victim's stolen credentials. By doing this, he can easily administer a large number of accounts, by leveraging the Twitter API.
Twitter Account Markets are a big problem on Twitter: first, an account with an inflated number of followers tends to look more trustworthy to the other social network users. Second, these services introduce spam in the network.
Of course, Twitter does not like this behavior. In fact, they introduced a clause in their Terms of Service that specifically forbids to participate in Twitter Account Markets operations. Twitter periodically suspends the OAuth applications that are used by Twitter Account Markets. However, since the market administrator has the credentials to his victims' accounts, he can go and authorize a new application, and continue his operation.
In our paper, we propose techniques to both detect Twitter Account Market victims and customers. We believe that an effective way of mitigating this problem would be to focus on the customers, rather than on the victims.
Since participating in a Twitter Account Market violates the terms of service, Twitter could suspend such accounts, and impact the market from the economic side.
Gianluca Stringhini is a PhD candidate working as research assistant at UC Santa Barbara. His research interests are Network Security, Botnets, and Spam Mitigation. You can follow him on Twitter at @gianlucaSB