The USS Malloc was a Federation starship in Starfleet service in the 24th century. The vessel was commanded by Captain Mirok and had several Vulcans among its crew. The Malloc was used for diplomatic missions.
In 2376, the Malloc visited the Sierra-Bravo 112 star system and noted that the planet Sierra-Bravo 112-II, visited three years earlier by Benjamin Sisko and the crew of the USS Defiant, had disappeared without trace. (DS9 - Rebels novel: The Liberated)