Those errors may also show up as result of faulty RAM.

As long as it does not reoccur, don’t worry. Maybe check your RAM when you have an hour to spare with memtest.
If it happens frequently and always shows Avast as problem, then you might want to try the Beta 6.0.1044 - you could do that anyway, it’s a very stable beta.

Please find downloads here, at the bottom of first post.