Is it a brass dragon or a bronze dragon that lives in or near Korvosa?
I have no knowledge of such a creature, except for Sabina Merrin's black dragon in the sixth installment of Curse of the Crimson Throne.
A little bit of research reveals a red dragon in the proximity of Korvosa from the Golariopedia):
"Glarataxus is a red dragon who has periodically plagued the towns and settlements near the Varisian city of Korvosa since 4569 AR. Absent for years, he will suddenly lay waste to a community with no perceivable reason and disappear just as quickly. His most recent attacks were on the communities of Veldraine, Korvosa, and Palin's Cove in 4674 AR. Attempts to negotiate with and appease the dragon have always failed, but this may be explained by a recent revelation: Glarataxus is deaf."
The dragon is also mentioned a handful of times in the timeline at the end the Guide to Korvosa.
After some persistent google searching, I found the name Thehydrax, who is mentioned in all of one sentence in Dragons Revisited. Thehydrax is also apparently brass. Hm.