Could there be a MOLE on the flight

I was reading another thread about WHAT WE KNOW and something just popped into my head. i'm not sure if anyone else ever came up with this theory but...is there a possibility that there could have been a mole on the plane, someone that works for Widmore?

Is it 100% confirmed that des caused the plane to crash when he allowed the countdown to go all the way without typing in the numbers? What if there was someone on the plane who worked for widmore that wanted it to crash so that he could make his way there?

What about Libby?

I have thought Cindy was something "Other" than just a flight attendant for Oceanic Airlines since the first season....

Even if they didn't cause the crash, there still could be a mole-like character involved. It seems that many people knew about the crash before it happened, it's very possible that Widmore placed someone on the plane. But the question is, did they survive?

There has always been this speculation with rumors circulating from Cindy to Hurley to Locke

Cindy would be a good person to suspect of being a mole.. She is now happily with the others..

If there was a mole, it would be someone with no flashback/past or parents, or with dubious history, anybody we know?

i agree with libby!!!!
they haven't shown her past..... she is the only one we haven't seen with a past. She was extremely willing to lend desmonde her boat. she only pops up in other peoples history's like hurley's when she was in the ward. But we don't know why she was there.... so she obviously is not very stable.

im sure thy will bring her back in more flashbacks

Yeah I think Libby may be the biggest mystery (as people go) in the show. Everyone else we know SOMETHING, even if there's alot to be known. Her, we know she just gave up her boat and she was in the mental hospital. We don't even know if she was admitted there or just spying on Hurley. Which brings up the question, is that why they fell for each other? because she planned it? AH! Was she even on the plane? She must've been but who knows.

If Widmore has access to information regarding which plane would be the one to find the island. Say, for example, if the DHARMA had found out some key data that could identify the plane in the future. If Widmore had that, he could simply set it up so that one of the people would be carrying out his plans without knowing it. We see characters with lots of drive and motivation that usually stems from some weird, mysterious circumstances. I don't think it's too much of a stretch to say one of the Losties could be in the service of Widmore, but I definitely say that if they are a MOLE, even they don't know about it.