McCammon will go straight into the squad for Bradford's clash with Darlington on Saturday.
Bantams boss Peter Taylor has also moved to sign Gavin Grant, who left Wycombe in March 2009, on a non-contract basis and the 25-year-old will also be in contention for a debut this weekend.
Meanwhile, a group of Bradford fans have raised £5,000 to help the club pay for James Hanson's transfer fee.
A Football League tribunal decided that the League Two side must pay Guiseley FC £7,500 for Hanson.
Source: Team Talk
Source: Team Talk