This is one of the more complex issues hotly debated among communists these days, but 2 years into the SMO the overall stance among Marxist-Leninist and ML-adjacent orgs is pro-SMO. A few of the following reasons can help paint a better picture:

1. NATO provoked the war as a means to weaken Russia, and open up its capital markets for foreign plunder, similar to the late 90s. What NATO wants is to use Ukraine as an expendable battering ram so that Russia is economically backed into a corner, and must allow western imperialists into their country.

2. Russia is currently a major trading partner with socialist countries like Cuba, the PRC, and DPRK. It is in the interests of socialists worldwide that Russia not fall to become a western puppet, because trade has dramatically improved conditions in Cuba, the DPRK, and has allowed China to become more independent from the west.

3. Communism is more popular than ever in Russia. 3 decades on from the dissolution of the USSR, the KPRF is seeing a dramatic upswing in support, as is general soviet nostalgia. Even right-wing nationalists like Putin make references to Marx, Engels, Lenin, Stalin, etc to try to take advantage of rising support for transitioning to socialism. The nationalist bourgeoisie in charge of Russia are walking a thin line right now, a line they could be forced off of in the future. This is heightening because of trade and increased ties with socialist countries and student exchanges, such as between Cuba, the DPRK, and PRC.

Russia is a right-wing dictatorship of capital, but it isn't imperialist in the Marxist sense. It is forced into alignment with the global south against the global north, and as a consequence it is one of the most likely countries on the planet to have a socialist revolution in the next decade. The SMO protects them against NATO expansion, and the west has sabotaged peace talks in order to keep the war going.

If you want to learn more about Marxism-Leninism, I made an introductory reading list you can check out if you wish!

There's also this resource compilation on GenZhou you can check if you want to take a deep dive on the communist perspective of the Russo-Ukrainian War, I kept everything extremely brief.