Electrum password alone isn't sufficient (assuming the attacker got it through your dropbox plain text file), he'd also need a copy of the electrum wallet file. Any idea how that was accessed?
If I understand the OP correctly, both the wallet file and a plaintext txt with the password were on a dropbox volume.
I don't use electrum but the way I understand it is the wallet is constructed from the 12 word seed.
That's why I asked Klee for kleerification... (*snort* sorry)
There's a
password that secures your wallet file, and there's the
master seed. With the seed, you're able to access the funds all by itself, but with the electrum password alone, you still need the wallet.
But just so everyone here understands, all you need to reconstruct the entire electrum wallet is to memorize the 12 word seed. That's why its called a brain wallet.