Russia has illegally annexed all foreign aircraft in its territory. Simply put if you own an aircraft and it was inside Russia at the time, it has been stolen.
For aviation risk exposure this is significant. Airlines needed to quickly understand what aircraft were located inside Russia at the time, and their maintenance status. Russia moved to prevent foreign pilots entering the country which meant that aircraft could not be stolen back to fly back to their home base. This has huge maintenance issues, Boeing and Airbus etc will no longer support maintenance and spare parts for these aircraft, meaning they will be cannibalised for spare parts from each other.
In terms of insurance, the insurance company, along with the owners, will be checking the terms and conditions of their policy in relation to terms and conditions, and whether they have to pay out. This will be a significant sum of money which will then result in higher aircraft insurance, and ultimately higher airfares.