In 2372, Jake Sisko was doing some research for a story that included a Kavarian tiger-bat, and tried to find out how it smelt. Kasidy Yates suggested that Quark might know someone who had been there, since she hadn't. (DS9: "For the Cause")
This planet was only mentioned in dialogue.
Benjamin Sisko stated Kavaria and the Dreon system to be neighbors, but Kasidy (perhaps maliciously) didn't agree. She claimed Kavaria was located too close to the Badlands for her comfort, although Sisko then implied Dreon was close to the Badlands too.
Kavaria might be the place of origin of Kavarian olives.
According to Star Trek: Star Charts (p. 46) and Stellar Cartography: The Starfleet Reference Library ("Federation Historical Highlights, 2161-2385"), there was a system named Kavaria, in which this planet might possibly have been located, in the Alpha Quadrant. The system's primary was a K-class star.