Accounts which have been affected will have the following in one of the most recent entries:
At the time this exploit was active, they could not be edited (changes would simply not happen). However, all embedding was turned off, and they should be fixable, now. Embedding from YouTube and RuTube has been returned, and other sites will become trusted soon, as well. The window of infection was somewhere between 1 and 2 hours.
For further details, please see this post.