Avira has just started reporting my unityplayerupdate.exe as a Atrap.gen trojan. The file is quarantined. Now what do I do? Does this mean someone is stealing my info or identity? Could it be a false positive?
Long Answer:
When checking against VirusTotal and Jotti, it seems that Avira percieves the web player plugin as TR/ATRAPS.Gen.
The trouble with all modern anti-viruses is that they detect stuff based on certain patterns. Most of the time the system works as it should, but every once and again it gets stuff wrong.
The easiest test is to check the file against those 2 online scanning services and check whether other anti-virus programs get the same result. In this case, it's only Avira, thus we can safely assume that it's a False Positive.
Short answer:
it's all good, no need to worry.
Here are the reports virustotal - jotti