We are unable to confirm whether this news is official.
A member of the forum, TrekBBS, posted pictures of what looks like the enemy. At first the poster said they were from The Christmas Special, but have since confirmed that they are from Episode 4, ‘What Are Little Boys Made Of?’
The pictures can be seen below:
Since these photo’s were posted online, apparently a crew member has tweeted that they’d heard news of leakages.