You could probably do an entire tumblr just devoted to the random made-up flags that people put on Wikimedia Commons. Somebody uploaded this flag seven years ago, and a few months later someone else helpfully labelled it as the “inofficial" flag of Zazaistan.
Zazaistan, in case you were wondering, is the name of a proposed homeland for the Zaza people, who live in eastern Turkey and are somehow related to the Kurdish people. As for this flag, it doesn’t seem to exist anywhere else on the internet, and FOTW shows three other flags for the region.
Does this flag exist in the real world? Probably not, but who knows?