On statistics flying large cargo aircraft is far more dangerous than passenger hauling. There are far fewer cargo flights than passenger flights and much higher accident rates. This is due to a number of factors, not least of which being the cargo itself is more hazardous and liable to gross errors that are just not encountered on passenger flights. The UPS 747 freighter lithium battery fire a prime example and the National Air 747 crash at Kandahar due poor loading are two of the most notable but it doesn't take long to find hundreds of accidents even in recent times. The loss rate of 747s alone is huge, with at least two crashed at Halifax due loading and runway issues. The other big issue is the working conditions, long hours at night, with a lot of monotony, meaning tired pilots making mistakes on load sheets and bad decision making, as highlighted in the Halifax crashes.
I'm not saying these things to exaggerate or scare, its to highlight the threats you face doing this type of flying, which is not commonplace in passenger operations.
Contract freighters into warzones are another thing all together, at present Russia is only at war with Ukraine, not its suppliers. In Afghanistan all aircraft were targets so contract and military alike were targeted and downed. A loaded large jet with weapons is an easy target and things would be much different if the war became global, and Russia lost the plot completely. Then there's just sabotage to these supply chains as well if it goes global. Let's face it none of us have lived through a global world war, so it's easy to forget what happens when everything becomes a fair game target. The US lost a lot of transports in Vietnam, Iraq and Afghanistan, just with local issues. Most don't even realise that the US lost almost 800 F-4 Phantoms and 31 B-52s in Vietnam because they are good at confusing the numbers.
Global war is unlikely, if we believe the news Russia has lost almost all it's capacity to fight its small front in Ukraine, so the idea they will spread to other fronts is very low anyway.