I have two reports (by Meta-Wiki and by e-mail) from people saying that they were following an interwiki link from en.wikipedia.org to azb.wikipedia.org but ended up on azbwiki's Special:AbuseFilter instead (even at localised version of that special-page url, which suggests they either got redirected or the address bar was updated by JavaScript afterward).

The report on Meta-Wiki was about https://en.wikipedia.org/wiki/Isabelle_de_Charri%C3%A8re. The interwiki link there (comes from Wikidata) points to https://azb.wikipedia.org/wiki/%D8%A8%D9%84_%D8%AF%D9%88_%D8%B2%DB%8C%D9%84%D8%A7%D9%86 which (given there is no colon) is definitely in the main namespace.

The Wikidata entry https://www.wikidata.org/wiki/Q123386 was not changed. The azb-language link was added last week, and not changed since then.

Regardless of the link not having changed since, and correctly pointing to a main-namespace page on azb.wikipedia.org, I too did get the response for Special:AbuseFilter when following this link:

https://azb.wikipedia.org/wiki/%D8%A8%D9%84_%D8%AF%D9%88_%D8%B2%DB%8C%D9%84%D8%A7%D9%86

However, after going back and trying again, I can no longer reproduce this.

@Quiddity was also able to reproduce the issue, but, like me, not a second time.