To defy Appel's claim, Bkav, a Vietnamese security firm uploaded a video on youtube and posted a blog where they claim that they have successfully duplicated someone's face to unlock iPhone X.
The Youtube video from the Bkav Corp -
The trick they used was very simple, they just made a composite mask of a 3-D-printed plastic frame, silicone nose handmade by an artist and simple paper cutouts.
The company says that they were able to hack into the ₹ 89,000/ ₹ 1,02,000 iPhone X for just 150 dollars (around ₹10000). They started constructing the mask as soon as they got iPhone X on Nov 5.
The blog post also says that “…after nearly 10 years of development, face recognition technology is still not mature enough to help secure computers and smartphones”. Bkav also wrote "Potential targets shall not be regular users, but billionaires, leaders of major corporations, national leaders, and agents like FBI need to understand the Face ID's issue,"
Previously, a similar attempt was made by wired.com. In the post, they where they tried to replicate the face of their lead gadget reviewer David Pierce but failed to bypass the Face ID feature in the iPhone X. The Wall Street Journal's Joanna Stern also made a silicone mask which failed do the trick.