North Korean hackers allegedly tried to steal Covid vaccine technology by hacking into Pfizer computers.
If the attempt had been successful, experts believe Kim Jong-un's despot regime would have tried to sell the information rather than use it to develop its own jabs.
The allegation was made by South Korea's National Intelligence Service - and is the latest in a string of reported attempts to steal the vaccine.
Last year suspected North Korean hackers tried to break into at least nine health organizations, including Johnson & Johnson, Novavax Inc, and AstraZeneca.
South Korea's intelligence agency said it had foiled North Korean attempts to hack into South Korean companies developing coronavirus vaccines.
The agency has reportedly found evidence of attempts to hack Pfizer, but has not provided any further information, according to the Yonhap news agency.
North Korea is often accused of turning to an army of hackers to fill cash-strapped government coffers amid international sanctions.
Just last week reports emerged claiming Kim Jong-un's agents had stolen more than $1.7 billion in cryptocurrency.
North Korea is expected to receive nearly two million doses of the AstraZeneca-Oxford Covid-19 vaccine by the first half of this year through the COVAX vaccine-sharing programme.
The secretive state has still not confirmed any coronavirus infections since the start of the pandemic.
But the NIS had said an outbreak there cannot be ruled out as the country had active trade and people-to-people exchanges with China before closing the border in early 2020.
Leader Kim Jong Un's wife, Ri Sol Ju, who hasn't been seen in public for more than a year, is keeping a low profile to avoid a risk of infection from Covid-19, the NIS believes.
