Adobe Flash apparently has a security hole that won't be fixed for several days yet. [h/t PlaceboMan]
Adobe Flash contains a vulnerability that may allow a remote,
unauthenticated attacker to execute arbitrary code on a vulnerable
system. Adobe Flash Player, Reader, Acrobat, and other products that
include Flash support are affected.
Here's the U.S. gubmnt site describing problem and what to do about it.