Pack's current deal at Cheltenham expires next month and he has rejected several offers from the club to extend his contract.
The 22-year-old is keen to play at a higher level than League Two and the news has alerted a host of clubs in League One and the Championship.
Pack has impressed for Cheltenham over the last few seasons and has been named in the PFA League Two Team of the Season for the last two years.
Charlton and Sheffield Wednesday are thought to be admirers of the goalscoring midfielder and are weighing up moves for the former Portsmouth youngster.
Cheltenham would be entitled to a compensation fee for Pack if he leaves the club because he is under the age of 24.