It's easily doable, I think the minimum connection time allowed is 50 minutes and even that is too much for KQ-KQ/KL flight, you are looking at 5 minutes walk to security and another 5 minutes after, security can take anywhere from 1-10 minutes.
On the downside, in the unlikely event you miss the connection you will probably have to overnight at NBO as most flights to Europe leave around the same time and then there is nothing further until the morning.