I don't think you're listening, and on top of that, making false assumptions.

Read what I wrote. The BitCoins were not sent out of my wallet. There is no send transaction. There is no security problem with my password. The RECEIVE transaction went as expected, then 12 hours later it was undone, and the same receive appears to have occurred on a new address I've never seen before, that has been magically added to my wallet. Now they're still showing up, but that new seemingly impossible transaction and address aren't getting any confirmations so I can't do anything with my BTC...

I've never used a cloud wallet before. I use a variety of locally-stored and encrypted wallets. I wanted to see how their service worked. Especially their little coin mixed send thingy.

What could cause that, I ask. It LOOKS like a Transaction Malleability goof has been applied to this transaction, and Blockchain.info is having trouble figuring out which way to go. Both addresses/TXIDs show that they were sent FROM the exact same set of addresses. It means that Transaction Malleability can be applied to any transaction, not just the ones you do yourself. And now it's forking around... Doesn't know which address to say it really went to. Odd, that I ended up with this new address in my wallet, that's a total damn mystery. I'm just looking for a theory on how this is possible.

EDIT: Back when I ran a bitcoind on my own server I did notice the entire wallet contents being sent to a new internal address from time to time when I sent a smaller amount... A seemingly totally unrelated transaction to a new address that it just made up. That was several years ago so it didn't pop into my head right away. Maybe this exposes something about how Blockchain.info's bitcoind works... Maybe they care and want to do something about it... Maybe it's a good thing? It seems to suggest that every wallet session on their machine is sandboxed with it's own bitcoind every time a person logs in. Knowing a little about blockchain.info wallets helps; they may be hosted, but they're not a collective system, they don't have passwords, and they send a backup to your email every single damn time you change something... Your wallet is encrypted with the password you give them at the time you create it, and that's how you manage to access it after that. They can't even read it themselves. It's been hours and still no confirmations for that TX... I also see no fee, which could be the reason.