Oil splatter under hood

#1
Recently purchased a used 2018 Corolla LE with 36k miles. I took a look under the hood and found no insulation and also spotted this oil splatter. The oil is tacky like it’s been there for awhile. Any ideas where it might have come from? 60B8238B-9F77-40D6-9658-5F2BB3B1CABA.jpeg
 
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