North korean hackers attempted to breach the systems of AstraZeneca last week , as the race to Covid Vaccine is heating up .

Hackers pretended to be job recruiters and used LinkedIn and WhatsApp to contact AstraZeneca employees with false job offers. Sources told the news outlet that the hackers then sent documents that they claimed were job descriptions but instead were written with harmful code to gain entry into the victims’ computers.

The hackers targeted a “broad set of people” like COVID-19 researchers, but it doesn’t appear that their break-in attempts were successful. AstraZeneca, Pfizer, Moderna have become the top three COVID-19 vaccine developers.

The hackers’ tools and techniques seemed to be that of a current hacking campaign that has been assigned to North Korea. Cyberattacks targeting drugmakers, health bodies, and vaccine scientists have escalated since the outset of the pandemic, as hacking groups try to get ahold of research and data about the virus.

Hackers from Iran, China, and Russia have previously endeavored to gain access into the systems of leading drugmakers and the World Health Organization. One source told Reuters that some of the accounts linked to the AstraZeneca attacks were registered to Russian email addresses as a way to deceive investigators.