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Hashcat Developer Discovers Simpler Way To Crack WPA2 Wireless Passwords (hashcat.net)
New submitter Woodmeister shares a report: While looking for ways to attack the new WPA3 security standard, Hashcat developer Jens "Atom" Steube found a simpler way to capture and crack access credentials protecting WPA and WPA2 wireless networks. The attacker needs to capture a single EAPOL frame after requesting it from the access point, extract the PMKID from it by dumping the recieved frame to a file, convert the captured data to a hash format accepted by Hashcat, and run Hashcat to crack it. Once that's done, the attacker has the Pre-Shared Key (PSK), i.e. the password, of the wireless network. Depending on the length and complexity of the password and the power of the cracking rig, that last step could take hours or days. "The main difference from existing attacks is that in this attack, capture of a full EAPOL 4-way handshake is not required. The new attack is performed on the RSN IE (Robust Security Network Information Element) of a single EAPOL frame," Steube explained. This makes the attack much easier to pull off, as the attacker doesn't depend on another user and on being in range of both the user and the access point at the exact moment when the user connects to the wireless network and the handshake takes place.
MAC whitelists do NOTHING for security.
First, anyone who can sniff the wifi traffic can see all the mac addresses.
Second, in Linux you can change your MAC to whatever you want with one command:
and use VLANs to ensure the guest network doesn't have access to anything but the internet.
Basic combinatorics: (size of character set)^(number of characters in password) is the size of the key space. To span an equivalent key space with just ones and zeros, you need log2(size of key space) bits. There are 95 printable ASCII characters: log2(95^63)=413 bits. The actual key derived from the passphrase is just 128 bits long, so that's overkill. You can max out the key strength with just 22 randomly (!) chosen characters from uppercase+lowercase+numbers. If your password is not completely random (it contains words, you typed "randomly", etc.), then you need more characters.
Was having fun with analogy.
The computer user password is not to protect against local access to the data.
PSK algorithm is not designed to protect against offline brute force campaigns. Well known property of PSK. It's why people have always had to chose increasingly absurdly long passwords to secure their APs.
You need to encrypt the files or entire drive like you are planning.
You need to use a secure authentication protocol like what's included with WPA3 to avoid susceptibility to offline brute force campaigns.
Only for WPA3 they chose a crappy authentication protocol out of the gate opting for a balanced PAKE when better (augmented) versions are readily available on similar terms.
Difference between balanced and augmented is a bit like the difference between a password file stored as plaintext or hashed.
If it's hashed (augmented) and stolen someone needs to crack it before they can login as you. If it's plaintext (balanced) as what was selected for WPA3 they can login as you immediately without cracking it.
A lifetime ago Cisco released an undocumented authentication protocol for username/password wireless authentication (LEAP) that was quickly revealed in all ways that mattered to essentially be MSCHAPv1.
At the time of release shortcomings of MSCHAPv1 were well known. Surely someone must have known yet they went ahead and did it anyway. While not nearly as egregious the same theme is being repeated with WPA3. Better algorithms with better properties are readily available yet they elect to go forward with the inferior one anyway.