Acts 10: And Peter opened his mouth and said: "Truly I perceive that God shows no partiality,  but in every nation any one who fears him and does what is right is acceptable to him.
This “fears him” and “does what is right” saves only because of the redemptive sacrifice of Christ. Jesus redeemed the whole world, thus salvation is open to the whole world because of him. It is not necessary for everyone to have heard of Christ to be saved, since salvation is a result of the redemption. And since the redemption has already happened, anyone may be saved through it. So, no one who is saved will be saved without Christ.
If you have not read the Catechism, here is the passage that addresses this issue:
Possible salvation of non-Christians: #s 846-848.
"Outside the Church there is no salvation"
846 How are we to understand this affirmation, often repeated by the Church Fathers?335 Re-formulated positively, it means that all salvation comes from Christ the Head through the Church which is his Body:
Basing itself on Scripture and Tradition, the Council teaches that the Church, a pilgrim now on earth, is necessary for salvation: the one Christ is the mediator and the way of salvation; he is present to us in his body which is the Church. He himself explicitly asserted the necessity of faith and Baptism, and thereby affirmed at the same time the necessity of the Church which men enter through Baptism as through a door. Hence they could not be saved who, knowing that the Catholic Church was founded as necessary by God through Christ, would refuse either to enter it or to remain in it.336
847 This affirmation is not aimed at those who, through no fault of their own, do not know Christ and his Church:
Those who, through no fault of their own, do not know the Gospel of Christ or his Church, but who nevertheless seek God with a sincere heart, and, moved by grace, try in their actions to do his will as they know it through the dictates of their conscience - those too may achieve eternal salvation.337
848 "Although in ways known to himself God can lead those who, through no fault of their own, are ignorant of the Gospel, to that faith without which it is impossible to please him, the Church still has the obligation and also the sacred right to evangelize all men."338