"He'll be suspended and you'll not see him officiating a game for a long time. He committed many mistakes," Bulgarian Football Union refereeing commission chief Nikola Dzhuganski said.
CSKA said Hristoskov failed to award two penalties and committed a number of other errors during the Cup match in Razgrad.
The 31-times Bulgarian champions appealed against "the extremely biased refereeing" and asked the BFU not to appoint Ristoskov for any of their matches from now on.
"I've never seen such a refereeing, it's not normal," said CSKA captain Ivan Bandalovski. "My desire to play football disappears after matches like this.
"You must be blind or crazy to not see what's going on."
Former UEFA referee Ristoskov, 41, was beaten up by three masked men outside his home a couple of weeks after refereeing the "eternal derby" between Levski Sofia and CSKA in 2006.
In 2008, he was banned by the BFU for committing errors in a domestic match and went to Austria to officiate in the lower divisions.
Last year, Ristoskov said he was offered $100,000 to help fix a UEFA Cup match between Azerbaijan's Neftchi Baku and Austria's SV Ried in 2007. He said he rejected the offer immediately.