I have seen several obituaries with this kind of wording: "He is very missed." It looks and sounds wrong, perhaps because "very" can modify adjectives ("He is very tall") and adverbs ("He walks very quickly") but it isn't used to modify verbs - one wouldn't say "I very miss him," so that "very" modifying a past participle sounds wrong, even though the past participle is acting as an adjective.
One might, however, say "I very much miss him", where "very" modifies the adjective "much", and "He is very much missed" sounds more correct.
But I haven't been able to find any reference which addresses this point, and automated grammar checkers say it's ok, which I find hard to believe. Is there a reference anywhere that could help?