"I'm very pleased to secure his services," manager Adrian Boothroyd said.
"He'll bring a wealth of experience and I know full well, having worked with him at Norwich, how much he will add.
"He's a leader on and off the pitch. He'll provide a further sense of balance to our squad."
"Over the last two seasons, he's been promoted twice with Norwich and West Ham and at 33 years of age he doesn't need reminding what it takes to succeed in this division.
"Malky will now be one of a number of centre-halves at this club fighting for the right to a first-team place.
"We need healthy and strong competition for places in every position on the park and Malky strengthens our defensive options."