Six games without scoring have left the Reds in deep trouble at the foot of the Championship where the bottom four clubs are in danger of being cut adrift.
Forest's financial position has been made clear for all to see over the past few weeks and Cotterill is not pinning his hopes on new signings to aid the fight against relegation.
"It may be possible to bring in a player or two on loan. But that is only a maybe. Because we have to find money that we have not got," he said, quoted in the Nottingham Evening Post.
"That is it. We have to find money. What has happened in the past, when Nigel Doughty was chairman, was that, whenever Forest were short or there was a chance to roll the dice, he has been able to buy someone.
"We don't have that any more. Any money that we have got to spend, we have to generate ourselves."
With players having to leave the City Ground before Cotterill can buy, the rumour mill is hotting up as January approaches. Chris Gunter is being linked with Fulham and Blackburn while Ishmael Miller is said to be interesting Middlesbrough.
Forest's task doesn't get any easier either with a New Year's Eve visit from Cardiff City their next fixture.
The Bluebirds lie 4th in the table after a 1-1 draw away to Watford on Boxing Day.