Understanding spammer infiltration in social networks and defending against collusion attacks

Like the Web, Twitter has presently become a target for link farming, where users, especially spammers, try to acquire large numbers of follower links in the social network. Acquiring followers not only increases the size of a user's direct audience, but also contributes to the perceived influence of the user, which in turn impacts the ranking of the user's tweets by search engines.
This project investigated link farming in the Twitter social network and then explored mechanisms to discourage the activity. We conducted a detailed analysis of links acquired by over 40,000 spammer accounts (suspended by Twitter) using a complete snapshot of the Twitter network from 2009. We found that link farming is wide spread, and that a majority of spammers' links are farmed from a small fraction of Twitter users, the social capitalists, who are themselves seeking to amass social capital and links by following back anyone who follows them -- in other words, by colluding with each other.
We also showed that a simple user ranking scheme that penalizes users for connecting to spammers can effectively address the problem by disincentivizing users from linking with other users simply to gain influence.



Understanding and Combating Link Farming in the Twitter Social Network
Saptarshi Ghosh, Bimal Viswanath, Farshad Kooti, Naveen Kumar Sharma, Korlam Gautam, Fabricio Benevenuto, Niloy Ganguly, and Krishna P. Gummadi. World Wide Web Conference (WWW), Lyon, France, April 2012.


An anonymized topology of the Twitter social network is already available, for details see this page.

The dataset we used in our study includes 41,352 spammer accounts which:
  1. were suspended by Twitter, as of February 2011, and
  2. had posted in the life-time at least one shortened URL which was blacklisted by the bit.ly or tinyurl services.




Saptarshi Ghosh is awarded a Humboldt Postdoctoral Research Fellowship
July 2014

Mainack Mondal, Bimal Viswanath and Krishna Gummadi, along with their co-authors win SOUPS distinguished paper award
July 2014

Juhi Kulshrestha receives Google Anita Borg Scholarship
May 2013

Cristian Danescu-Niculescu-Mizil wins WWW best paper award
May 2013