What's the official Catholic position regarding the literal truth of incidents described in the Old Testament?

I am a (rather heterodox) Catholic, so I don't know whether and how my Answer counts.

I simply wanted to enter a comment in reply to Paul Chernoch, regarding the link he provided to the article The Killings of Numbers 31 (@apologeticspress.org) by AP Staff.

But, having read the article, I found what I believe to be a conflict (something close to a contradiction). Here is what the article says, at some point:

However, to allege that the God of the Bible is some sort of “monster” for ordering Israel to destroy the inhabitants of Canaan exhibits an ignorance of biblical teaching. Those inhabitants were destroyed because of their wickedness (Deuteronomy 9:4; 18:9-14).

Looking at the cited passages of Deuteronomy we read, in particular:

... it is (...) because of the wickedness of these nations that the Lord is dispossessing them before you (Deut 9:4) ... it is because of such abhorrent practices that the Lord your God is driving them out before you. (Deut 18:12) [emphasis added]

But if we read from Numbers, cited in the OP Question, we read:

¹⁷ Now therefore, kill every male among the little ones, and kill every woman who has known a man by sleeping with him. ¹⁸ But all the young girls who have not known a man by sleeping with him, keep alive for yourselves. (Num 31:17-18)

Conclusions

1. There is an evident contrast between Deuteronomy 9:4;18:12, where the Lord promises to "disposses", to "drive out" the Canaanite nations, and Numbers 31:17-18, where Moses commands to kill and plunder the Midianites. If the reader is ready to say, "Ha, but that was Moses", read on, in particular Numbers 31:25-30 (Disposition of Captives and Booty), where the Lord seems to speak more like a mafia boss than ... the Lord God Almighty.

2. Maybe it is precisely with (not only these horrors, but mainly) these contrasts in mind that the Catholic Church tried (tried ...) to downplay these narrations as "exaggerations and hyperbole".

St. Thomas Aquinas, Summa Theologica I q. 1 a. 9 co., shows that Holy Scripture uses metaphors and similes:

It is befitting Holy Writ to put forward divine and spiritual truths by means of comparisons with material things. For God provides for everything according to the capacity of its nature. Now it is natural to man to attain to intellectual truths through sensible objects, because all our knowledge originates from sense. Hence in Holy Writ, spiritual truths are fittingly taught under the likeness of material things. This is what Dionysius says (Coel. Hier. i): "We cannot be enlightened by the divine rays except they be hidden within the covering of many sacred veils." It is also befitting Holy Writ, which is proposed to all without distinction of persons—"To the wise and to the unwise I am a debtor" (Rm. 1:14)—that spiritual truths be expounded by means of figures taken from corporeal things, in order that thereby even the simple who are unable by themselves to grasp intellectual things may be able to understand it.

It is rare that the Catholic Church explicitly defines a proper interpretation of a particular passage in Scripture. Typically, an exegete would look to the Church Fathers and to the typical interpretation of theologians through the ages in order to determine if his or her interpretation is orthodox. As far as I know, whether or not hyperbole is used in Old Testament passages about God willing violence is a matter open to individual belief. I have heard some people claim that these passages are referring to God's passive will as well, that He permitted the violence while not actively willing it, but it is recorded as an order from God because He is using it to bring about a greater good; the founding of Israel, or the rebuilding of Israel, etc.

I would be wary of people who claim there is an "official" Catholic stance on the interpretation of a particular passage of scripture unless they can point to a Church Council or a Papal Encyclical. Keep in mind also that these sorts of documents usually condemn one particular interpretation of scripture as false, leaving the door open on any others not explicitly condemned, rather than the other way around. So it's more likely you would find a Church Council stating that it is wrong to interpret, eg John 1 as saying that Jesus was a god among many (due to the lack of definitive articles in Greek), rather than finding a council that gives the "official" interpretation of John 1.