There is no present perfect in French. The verb is mettre used at the passé composé.

The passé composé is built with an auxiliary verb conjugated at the present and a participe passé.

Because the auxiliary verb here is avoir, the rule is to have the past participle to agree if the COD (complément d’objet direct) is located before it. That is the case here: les is a pronoun referring to les lunettes. The word lunettes is both feminine and plural thus the past participle is mises.

If the COD is located after the past-participle, the is no agreement, compare:

…a mis les lunettes…

and

…les a mises…

See Accord du participe passé avec un pronom relatif

The other answer is true, but if you want more details: This sentence is equivalent to: Quelqu’un a forcément mis les lunettes quelque part. Les lunettes in this case is a complément d’objet direct and féminin. In your sentence, les is replacing lunettes so les is a complément d’objet direct. Since verb mettre is conjugated with auxiliaire avoir in the past, you must do the accord en genre et en nombre meaning masculin et féminin (male and female) and singulier et pluriel (singular and plural).