The ex-Warriors forward will remain at the club through 2026 after inking a one-year contract extension following a strong first season at Belmore.
Along with Kurt Mann, Kurtis Morrin, Bailey Hayward and Jaeman Salmon, Curran helped execute on plans to take a lightweight, mobile middle forward rotation up the ladder in Cameron Ciraldo's second year as coach.
The 24-year-old started mostly from the bench in 24 games at his new club and finished the season with career-high totals in average run metres and post-contact metres.
"We are pleased Josh has extended his time with the Bulldogs," said Canterbury general manager of football Phil Gould.
"He has clearly played some of his best football this year and become an integral part of the team as both a major contributor on and off the field."
Elsewhere, outside back Max Feagai will leave St George Illawarra to join the Dolphins on a two-year deal from 2025.
Max Feagai signs until 2026 �— The Dolphins (@dolphinsnrl) #PhinsUp pic.twitter.com/y85G96IrZdOctober 2, 2024
Feagai cemented himself as a week-in-week-out NRL player for the first time in the back-half of the 2024 season after an injury to Jack Bird.
His departure leaves the Dragons down another outside back for Shane Flanagan's second season as coach, with Bird and Zac Lomax also out the door and only Valentine Holmes signed as a replacement thus far.
It comes as Newcastle tie middle forward Mat Croker to a new one-year deal for next season.