Malicious and Low Credibility URLs on Twitter During the AstraZeneca COVID-19 Vaccine Development

We investigate the link sharing behavior of Twitter users following temporary halt AstraZeneca COVID-19 vaccine development in September 2020. During this period, we show presence malicious and low credibility information sources shared on messages multiple languages. The URLs, often shortened forms, are increasingly hosted content delivery networks cloud hosting infrastructures not only to improve reach but also avoid being detected blocked. There potential signs coordination promote both URLs Twitter. Our findings suggest need develop a system that monitors low-quality times crisis.