North Korean hackers attempted to breach the servers of the U.S.-based vaccine manufacturer Pfizer, and its German partner BioNTech, in hopes of gathering scientific data that could be used to manufacture bootleg copies of a COVID-19 vaccine to sell on international black markets, according to intelligence officials in Europe.

North Korea’s intent was likely to raise funds in foreign currency. The hermit dictatorship’s domestic currency is mostly worthless outside its borders.

Two European security officials briefed on cyber-operations told Insider the attempted intrusion was likely an official North Korean operation to gather scientific data on Pfizer’s COVID-19 vaccine, one of just three vaccines so far approved for emergency use by the World Health Organization. Both officials said the attempt was connected to November’s announcement of multiple hacking intrusions via Microsoft network infrastructure.

“It clearly was an information-gathering attempt rather than a malware– or ransom-style attack. I will not get into technical details but we have developed plenty of experience with each type of attack,” said a European official, who would not be named because of the extreme sensitivity of the situation.

“North Korea will have physical access to Pfizer vaccines long after they’ve seen Chinese or Russian versions. But they want to decide which will be the easiest to bootleg and transport for the black market,” said the official, pointing out that both Russia and China have promised millions of doses to North Korea for free, despite the country’s claim it has never had a case of COVID.

“So they wanted to take a look to see if the Pfizer vaccine would be a viable dose to copy,” added the official. “We are not giving out any information on whether the hacking attempt succeeded but if it had I’d suspect the Pfizer vaccine would provide too many manufacturing and storage problems compared to the Russian or Chinese vaccines.” The Pfizer vaccine requires two types of refrigeration; the AstraZeneca version needs only a normal fridge.

When asked if North Korea would be trying to sell a bootleg of some sort, the source confirmed without a doubt, considering North Korea’s long history of counterfeiting, bootlegging, drug-dealing, and arms-smuggling through its embassies around the world.

Hacking alone provides massive amounts of income to the regime, according to indictments last week by U.S. authorities against a ring of North Korean state-linked hackers accused of stealing $1.3 billion from various targets.