There is something called "shortened causative form" in Japanese. For example you can say 走らす instead of 走らせる. See Tae Kim's guide on this topic.
Although the article says the shortened causative form is rare and slangy, it's not rare nor rough when godan verb's causative-passive form is concerened. To my ears, the shortened causative-passive form (-asareru) sounds considerably more common and natural than the "standard" causative-passive (-aserareru), even in formal writings.
- 書かされる is more natural than 書かせられる
- 笑わされる is more natural than 笑わせられる
- 悩まされる is more natural than 悩ませられる
(I think this does not apply for shortened causative of ichidan verbs and godan verbs with su-ending; 食べさされる and 話さされる are ungrammatical)
Some shortened (non-passive) causative forms are widely used without sounding rough/slangy (eg 頭を悩ます問題, 犯人を泳がす, 醤油を切らす), and dictionaries often list them as separate transitive godan verbs. In Japanese, the borderline of "the causative-form of an intransitive verb" and "a transitive verb" can be sometimes blurry. Nevertheless, I think it's not wrong to say 悩まされている is causative-passive(-progressive).