Isn't it obvious?
Putin wants to incite North Korea to stir up trouble in East Asia and drag China into a war through the <China-North Korea Friendship, Cooperation and Mutual Assistance Agreement>, thus reducing the pressure on Russia.
North Korea also wants to use the time when the US is being held back by Ukraine and Israel to gain some advantage.
As for China, we are under serious threat from the Philippine Navy and Air Force in the South China Sea. If North Korea stirs up trouble on the Korean Peninsula, we may not be in a position to help them with the aftermath.
As for Japan, the Japanese are busy solving their economic problems, and the Japanese Government has turned a blind eye to the missile tests of the DPRK and has not responded substantively.
As for South Korea, after the visit of the American envoy to South Korea, the new South Korean president was restrained and they are now limiting their confrontation with North Korea to the realm of propaganda warfare. They are said to be throwing poop at each other's soldiers' heads with balloons.
btw: Who else in the Vietnamese Politburo is a southerner now? Who will replace Nguyen Phu Trong? Is it Tô Lâm? Do public security and the military belong to the same system in Vietnam?