Covid-19 vaccines, vaccine passports and faked negative test papers are being sold on the darknet.
Prices range between $500 (£360) and $750 for doses of AstraZeneca, Sputnik, Sinopharm or Johnson & Johnson jabs.
Fake vaccination certificates are also being sold by anonymous traders for as little as $150.
Researchers say they have seen a “sharp increase” in vaccine-related darknet adverts
The darknet, also known as the dark web, is a portion of the internet that is only accessible through specific browser tools.
Researchers at cyber-security company Check Point have monitored hacking forums and other marketplaces since January, when vaccine adverts first appeared.
They say the number of adverts they have seen has tripled to more than 1,200.
Sellers of vaccines appear to be from the US, UK, Spain, Germany, France and Russia.
The team found multiple adverts in Russian cyrillic text as well as in English.
The vaccines advertised include the Oxford-AstraZeneca at $500, and Johnson & Johnson and Sputnik each at $600, and Sinopharm at $750.
One seller is offering next-day delivery, saying: “For overnight delivery/emergency leave us a message.”‘
‘Buy two get one free’
Another advert on a hacking forum is offering fake negative tests and reads: “We do negative Covid tests, for travellers abroad, for getting a job etc. Buy two negative tests and get the third for free!”