The magazine Dabiq is generally thought to be a propaganda magazine produced by the proponents on Islamic State of Iraq and the Levant (a.k.a. ISIS, ISIL or IS).
The Islamic State (ISIS) regularly puts out a glossy propaganda magazine aimed at recruiting jihadists from the West. It is sophisticated, slick, beautifully produced and printed in several languages including English.
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'Dabiq' as it is called, bills itself as "a periodical magazine focusing on the issues of tawhid (unity), manhaj (truth-seeking), hijrah (migration), jihad (holy war) and jama'ah (community). It will also contain photo reports, current events, and informative articles on matters relating to the Islamic State."
However, an answer on a Politics.SE question suggests:
If you read their magazine "Dabiq", you even may come under first impression that it is anti-ISIS propaganda.
Is the magazine produced by ISIS? Or is it a hoax by ISIS's opponents to discredit ISIS along the lines of the Russian secret police producing The Protocols of the Elders of Zion?