I recently received this flag as a gift but I am completely stumped as to what it is (the person who gifted it to me does not know either). The flag appears to be from this eBay listing and is simply labeled as F-1936-B. I have tried reverse image searching and searching for terms such as "white stripe USSR flag" but have found nothing.
It looks like a variation of the 1936 USSR flag. The F is for enumerating, 1936 is when it was adopted, B means the variation (A is the official 1936 Soviet flag)
However, I couldn't find it on the internet