Team captain Todor Yanchev was moved to the coaching staff in the clearout, which the Sofia-based club said was made because of lack of effort and unprofessionalism.
Algeria keeper Rais M'Bolhi, Curacao defender Civard Sprockel, Cape Verde defender Nilson and experienced Bulgaria midfielder Hristo Yanev were among those who were fired.
CSKA were lambasted by the local media after they were beaten over two legs by Slovenia's Mura 05 on the away goals rule after a 1-1 draw on aggregate.
CSKA, the most successful Bulgarian club with 31 league trophies, reached semi-finals in Europe three times between 1967 and 1989 but have struggled to revive their former glory in recent years and have not won the domestic title since 2008.
- Hristo Yanev