It seems very dramatic. Two drones and one small explosion were filmed over a tower of one of the Kremlin buildings. Without providing any evidence, or giving any reason why such a thing might be true, Russian authorities blamed Ukraine, claiming that it was an assassination attempt directed against Vladimir Putin.

The Russians have lied about every major event in this war, and have always presented themselves and their president as its victim. So we would be justified in doubting what they say.

Ukrainian authorities deny having anything to do with the drones over the Kremlin. They would have nothing to gain from such an operation, and very much to lose. Their allies already deny them weapons on the grounds that they might use them to attack Moscow. Such a high-profile Ukrainian attack would thus hurt Ukraine by making it less likely that they get the supplies they need to win the war and stop the killing in their own country. The question of Ukrainian motivation tends to lead us back to the Russians.

Even assuming the Ukrainians are lying and have misjudged their own interests: Could they send a drone over the Kremlin? It seems unlikely. Moscow bristles with anti-air defense, and the Kremlin would presumably be the space that is most carefully protected. That would tend to suggest that the people who sent the drones over the Kremlin were the same people who were in charge of the air defenses. So asking about Ukrainian capability also leads us back to the Russians.