At Black Hat: A free tool for spear phishing Twitter

A spear phishing tool to automate the creation of phony tweets – complete with malicious URLs – with messages victims are likely to click on will be released at Black Hat by researchers from ZeroFOX.

Called SNAP_R (for social network automated phisher with reconnaissance), the tool runs through a target Twitter account to gather data on what topics seem to interest the subscriber. Then it writes a tweet loaded up with a link to a site containing malware and sends it.

More on Network World: FBI needs to beef-up high-tech cyber threat evaluations says DoJ Inspector General+

The researchers – John Seymour and Philip Tully – say SNAP_R lets them scale up phishing tries on Twitter accounts. It takes five to 10 minutes to write a single spear phishing email, for example, but it takes a matter of seconds or minutes to generate thousands of spear phishing tweets, depending on how much hardware they throw at the problem.

The manual phishing has a 40% to 45% click-through rate, while their automated method garners about 33%. But because of the speed with which the tweets are generated, the net return is much greater. “It’s slightly less effective but it’s dramatically more efficient,” says Seymour.

Twitter accounts are a good place to try spear phishing because of the combination of language used, APIs to rich data and use of shortened links. Because tweets and short and informal, the language doesn’t have to be perfect and messages are so short that victims might forgive mistakes that might tip them off if they occurred in an email, Tully says.

Twitter APIs let the tool auto-post as well as collect significant data about the victims so it’s easier to write tempting tweets. And the shortened links mask the actual URLs, which might raise red flags about the authenticity of the tweets, he says.

+More on Network World: Stuxnet the movie: The U.S. has pwned Iran+

SNAP_R triages users by checking how active their accounts are and seeking clues about what they do for a living. Inactive accounts indicate someone with little prospect for even finding the tweets. Career information can indicate whether the person is the right type of person to receive the tweet and also to determine what subject matter might entice them, Seymour says.

The tweets themselves can be fashioned using a Markov model that ties it to a timeframe. So if a person is interested in the Rio Olympics, it wouldn’t pay to write a tweet about them in December, but they might be an excellent topic for July.

They can also be fashioned using a neural network model that is trained how to compose tweets by having it digest millions of tweets beforehand. All it needs is to find a topic to tweet about. It can also write in any language. The goal is for the tweets to be indistinguishable from tweets written by a person.

For enterprises, the tool can be used for internal testing to find out how susceptible workers are to falling for the phony tweets, says Evan Blair, chief business officer for ZeroFOX. It’s never dawned on a lot of Twitter users that they could be phished in a tweet, so just making them aware of the problem could help reduce the number who fall for it, he says.

The researchers acknowledge that the tool could be used for spear phishing, but they’ve included a defect to mitigate the malicious use of it. For verified white-hat researchers they say they can remove the defect.

SNAP_R runs on Ubuntu and OS X, and operates in three phases. The researchers crafted it to work with Twitter, but similar tools could be made for other social networks.

Writing the tool took Seymour and Tully, both Ph.D. students specializing in data science, about two months.