Congo-Brazzaville top African Nations Championship Group D after drawing 0-0 in Agadir with Angola, who also progress to the quarter finals to meet Nigeria.
In the group's other fixture, Burkina Faso drew 1-1 with already eliminated Cameroon to fall short of the final eight.
Congo were already through heading into their final fixture after winning both of their first two fixtures, and will now meet Libya in the quarters.
Both they and Angola advance without conceding a goal.
Burkina Faso found themselves already up against it heading into the final round of fixtures, knowing that they needed a win, an Angola defeat and a three-goal swing to progress.
The Stallions did take the lead in the 42nd minute of a tepid first half, when Mohamed Sylla tapped home from close range after stand-in Cameroon stopper Derick Fru Anye fumbled the ball into his path.
Any hopes the West Africans had of kicking on from the opener, however, were extinguished seven minutes after the pause.
Black Williams Ngoundo Bile sent in a fine cross in one of the game's few moments of quality, and Patrick Moukoko was on hand to volley home Cameroon's first goal of the tournament.
The draw leaves Cameroon in bottom place on one point, while Burkina Faso, with two, will rue not building on their rugged opening draw with Angola.