The Iron remain 22nd on 31 points, four behind Crystal Palace on 35. Ian Baraclough's men have one game in hand, a must-win home game against bottom club Preston North End.
Middlesbrough are 20th after their draw with Forest, although they were so close to claiming all three points at the Riverside Stadium.
Forest looked set to suffer a first defeat on Teesside in 28 years when Scott McDonald fired the hosts ahead in the 51st minute.
Goalkeeper Lee Camp pulled off a series of fine saves to keep the visitors in the game, however, and his efforts were rewarded in the 92nd minute as Dele Adebola pounced on a loose ball to scramble the ball past Jason Steele from eight yards.
Boro remain 20th and will wonder how they failed to convert their second-half display into three points.
Forest move up to fourth in the table as a result and now sit three points behind second-placed Swansea.
Derby County failed to put further distance between themselves and the relegation zone as they were beaten 3-1 at home by Doncaster Rovers.
The victory for Rovers came via goals from two former Iron players, with Billy Sharp netting twice and Joseph Mills adding a third.
Championship side Reading reached the quarter-finals of the FA Cup with a 1-0 win at the Premier League side Everton.
Matt Mills, the Royals captain, struck the only goal at Goodison Park as they shocked the Merseysiders to claim a place in the last eight for the second successive season.