This attack could pose a serious security threat. You should take immediate action to stop any damage or prevent further damage from happening.
The signature detects scams originating from Twitter. These scams can either be Fake offers, fake surveys or links leading to fake videos.
Twitter only allows to share 140 characters. All URLs are shortened by twitter itself. This allows the scammers to create a small and attracting text along with the shortened URL(thus hiding the original URL). Once the link is clicked by the user, he/she will be redirected to the scam page which can also steal user details and lead to cyber crime.