It is sealed from leakage out of the electrical connector. It is leaking between the acuator and the cover. You can take out the 5mm allen bolts and clean the surfaces. Apply a small film of Hylomar or equiv. to both surfaces and reassemble.
We use the factory sealant for this, but most do not have access to this $15 dollar tube of sealer. The Hylomar will work fine.
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