Recently, I have scanned nearby wireless networks with airodump. I have discovered five networks transmitting on channel 3. MAC addresses of access points (BSSIDs) transmitting on channel 3 differ only in last two hexa digits and a signal level (PWR) reported by my WiFi card is almost same for all BSSIDs.
$ sudo airodump-ng wlp3s0
Picture 1 - Wireless Networks of Caffe Geo Guru
The following three ESSIDs have caught my attention.
1) Heslo do siete caffe.geo.guru
2) zistis rozlustenim sifry
3) qnw fv qboer cvib
In fact, the ESSIDs represent a cryptography challenge created for customers of caffe.geo.guru. Once the challenge is successfully solved a customer gains a password for connection to the wireless network with ESSID caffe.geo.guru.
Note: The first two ESSID are written in Slovak. Their English version is below.
1) Password to network caffe.geo.guru
2) can be gained by decoding words
3) qnw fv qboer cvib
The third ESSID represents an encoded password. Obviously, letters are substituted in ciphertext which let us to the assumption that ROT cipher is used. Using ROT13 cipher on the encoded text 'qnw fv qboer cvib' gives us a required plain-text password 'daj si dobre pivo'. The English translation of the phrase may be 'order a good beer'.
Picture 2 - Inside Keška – Geocaching Shop&Cafe
The command below replaces every letter in the text with the 13th letter after it in the alphabet.
$ echo 'qnw fv qboer cvib' | tr '[N-ZA-Mn-za-m]' '[A-Za-z]'
daj si dobre pivo
Very interesting!!