Confidence: It's likely to be this, but I can't be certain.
Notes: Can only think of three species which have this general colouration and the kind of pattern that can be seen near the termen of the forewings: Pandemis corylana, Acleris forsskaleana and Aleimma loeflingiana. The wing shape only really fits the first of these. I assume that the forewings have been significantly rubbed and that the remainder of the pattern has been lost. This seems more likely than that this was naturally as plain as this.