If it has all the right symbols on it then it's passed safety certification.
Cause no one in a third world nation would EVER dream of putting such markings on a device that hadn't actually passed safety inspections!
If you bought the supply from a reputable in-nation dealer (like amazon themselves) it's probably OK.
If you bought it from one of the dealers that have sprung up importing things direction from China (and etc), the low prices that you get by bypassing customs probably means that you bypassed real certifications as well. It might be OK, and it might not. Measure it, look at it, make your own judgements.