The ban does not apply this season but would take effect the next time that the Qatari-owned club qualified for European competition in the next four years, UEFA said in a statement.
The ban will be extended for a further season unless Malaga can prove by the end of March that they have settled outstanding payments to other teams, staff and tax authorities. Malaga have also been fined 300,000 euros.
In a strongly worded reaction, Malaga accused UEFA of making them a "scapegoat".
"The measures it seeks to adopt against the club are completely disproportionate and unjustified considering the club's situation," they said in an emailed statement.
Malaga, who are in the last 16 of this season's Champions League, have the right to appeal to the Court of Arbitration for Sport, an independent body based in Switzerland.
The club said they were poised to reach an agreement with the Spanish tax authorities on outstanding payments as funds previously blocked by UEFA had been released.
Cash owed to La Liga rivals Osasuna and Malaga's own players was also being paid off according to plan, the club added.
Owner Sheikh Abdullah Bin Nasser Al Thani had shown he was committed to the club by recently making a cash injection of more than 7 million euros, Malaga said.
The punishments meted out to Malaga and seven other clubs underline that UEFA is serious about enforcing Financial Fair Play rules that are being phased in.
Croatian clubs Hajduk Split and Osijek, Romania's Rapid and Dinamo Bucharest and Serbia's Partizan Belgrade also face one-year bans unless their bills are settled by March.
Serbia's Vojvodina and Arsenal Kiev of Ukraine were both fined.
UEFA's rules mean that all clubs will ultimately have to move towards balancing their books or face exclusion from European competition.