The warnings come from depraved extremists in private chat groups on the encrypted messaging app Telegram. They call on lone wolf terrorists to carry out blade attacks and car rammings in the Ukrainian capital, which is hosting the final between holders Real and five-times winners Liverpool.
Ollie Wiltshire, Director of Intelligence for Europe and the Americas at Max Security Solutions, in Tel Aviv said: "Although ISIS likely does not have the capabilities to carry out a mass casualty attack in Kiev, the push from their supporters to threaten high-profile football matches should be taken as an indication of their intentions to target the 2018 World Cup in Russia.
"We know that cells are operating in many major Russian cities and that the Russian security services have already arrested a series of militants looking to attack the games.
"The threat of an Islamic State-linked militant attack targeting the tournament in Russia is elevated."
Thousands of Liverpool and Real fans are expected to travel to Ukraine – a country which is harbouring hundreds of fleeing jihadis.
Around 500 mainly Russian ex-ISIS fighters who have fled the frontline in Iraq and Syria and are dodging security services in their homeland.
The brainwashed extremists have used lax border controls to slip into Ukraine – often via Turkey.
Last night ISIS propaganda chiefs issued a direct threat to strike at the showpiece match in Kyiv next week.
A disturbing poster released on ISIS-supporting internet channels shows a heavily-armed fighter standing above the 70,000-seater Olympiiskyi stadium.
Another poster shows a fighter in civilian clothes with a rifle strung across his back and has the warning: "We will be there…Islamic State.
Following the collapse of ISIS in the Middle East, leaders have called for lone wolf attacks on high profile targets.
Observers in Ukraine believe there are 400 to 500 ex-jihadists from Syria and Iraq in hiding there.
The majority it's thought are Russian-speakers from Russia or Central Asian states.