Network authentication and connection behaviour

Strange thing happening here. The Laptop automatically connected to a neighbour's Wifi network, though it (Neighbour's Wifi) is PSK passkey protected and blocks any attempts to enter a random key. Looks like Elive just hacked my neighbour's wifi without any input from my side!.

The only logical explanation for this is that an old password left by the neighbour's teenage kids when they come to play with my kids on my computor on my harddisk was detected by the fresh install of Elive and kept and is being used automatically. Potential network security issue when disposing off your old computors password remain hidden on it

Exactly that, those passwords will be remembered unless they're set to be forgotten.

I would start with taking a look at /etc/wpa_supplicant/wpa_supplicant.conf. Unfortunately there is no log of the access. A version control system would be great.
Here should be the "keystore file" for your networks.

I know there is malware, that hacks silent into nearby networks to spread. But not for Linux. The needed prerequisites would be too much, to do it silently in the background. The Last router I know is a Alice (Telefonica Germany) box from roundabout 2005, that generates the PSK from the MAC address ... very uncommon.