The Algemeiner contacted UNESCO about this:
When contacted directly by the Algemeiner for comment a UNESCO spokesperson replied, “UNESCO acknowledges that there was indeed an important and regrettable error in the chapter devoted to Arab States in the UNESCO Science Report published in 2006, which refers to Maimonides as a Muslim scholar,” they said. “Despite the vigile [sic] of our editors, errors unfortunately do occasionally occur.”That's not quite an apology.
The representative declined to comment further.
While the acknowledgement is welcome, in the context of UNESCO declaring Rachel's Tomb to be a "historic mosque" - a provable lie - and other anti-Israel biased statements it has made recently, one wonders if a mistake like this is more than just a mistake.
UNESCO must have known how offensive this Maimonides gaffe was, so to shrug it off as "just one of those things" hardly seems an adequate response.