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34

The schemes you mention are protocols for securing 802.11x traffic over wireless networks. They don't mandate how the AP password is encrypted or hashed during storage. However, the security of the protocol does rely on making the key secure. WEP relies on a broken RC4 implementation and has severe flaws in various aspects of its protocol which make ...


27

From a security perspective, I think you are asking the wrong question. WPA2 is the basic answer. But it's entirely incomplete! A more complete answer will view WPA2 as one component of your wireless network defence. Of course there's strong encryption methods using certificates/vpn etc but these are too difficult for most people to set up and are usually ...


25

In a nutshell, WPA2 is currently the most secure wireless security scheme. Personal and Enterprise It supports two main modes of authentication, known as WPA2-Personal and WPA2-Enterprise. The former utilises a pre-shared key (PSK) and is generally considered to be most suitable for home networks, whereas the latter is 802.1x which requires an ...


19

Yes and no. They may not have your password in plaintext, but they have enough to potentially guess it and verify that guess (i.e. offline brute forcing). WPA2 authentication is performed through a four-way handshake. Instead of just sending your password in plaintext to any access point you connect to, this handshake ensures that unless both parties ...


19

Anyone who witnesses the association process of a new client can eavesdrop on their connection. As reassociations can be forced by a rogue host that sends a forged disassociation packet in the name of the target, it is practically always possible to listen in on all connections on a WPA(2) network with a preshared key. You can even try it for yourself in ...


14

The PSK variants of WPA and WPA2 uses a 256-bit key derived from a password for authentication. The Enterprise variants of WPA and WPA2, also known as 802.1x uses a RADIUS server for authentication purposes. Authentication is achieved using variants of the EAP protocol. This is a more complex but more secure setup. The key difference between WPA and WPA2 ...


11

This book is a very good resource on wireless security. This section explains the details of the four-way handshake, but you really need to read the whole chapter to understand it. Both WPA2-PSK and WPA2-EAP result in a Pairwise Master Key (PMK) known to both the supplicant (client) and the authenticator (AP). (In PSK the PMK is derived directly from the ...


11

The short answer is that WPA2 is the only secure protocol. But it's secure only if WPS (WiFi Protected Setup) on the access point is disabled. WPS is broken, an access point with WPS enabled is crackable, no matter what kind of WiFi protocol it uses. For more info: How to crack a WPS enabled WiFi network Sadly, WPS is enabled by default on the ...


11

Instead of continuing in the comments, I think I will just answer your real question, which I understand to be - why is using WPA/WPA2 Personal with a public SSID and Passphrase not more secure than having an open network, and why doesn't WPA/WPA2 Enterprise work in the coffee shop scenario. If the passphrase was public (as it would be in this scenario) ...


10

No. It doesn't matter how long your passwords are because that value is never transmitted during the WPA-PSK Key Exchange. Instead a CMAC is calculated based on the secret key, the client and server id, as well as client and server provided large random values. Regardless of how large your password is the resulting CMAC for WAP2-PSK will always be 128 ...


10

TL;DR: FaceNiff probably exploits WPA's "Hole 192" and uses ARP poisoning to set up a Man-in-the-Middle attack. The steps, in short, are: Eve uses the Group Temporal Key (GTK) to inject ARP packets into the network, with the network's gateway IP paired to her MAC address. Clients register Eve's MAC address as their new gateway. Clients send packets ...


10

Not alone like a WPA/2 PSK attack, where you can simply capture the handshake and bruteforce. You'll need to capture the "Enterprise" authentication attempt. To do this, you can perform an "Evil Twin" attack that captures the authentication attempt, which can then be subsequently cracked. Here's an excellent presentation by Matt Neely of SecureState that ...


10

Short answer is: use WPA2. WPA would be somewhat tolerable, but WPA2 should really be preferred. Do not use WEP, which is not really better than nothing (arguably, WEP is worse than nothing, because it gives to users the impression that security is happening, whereas it is not). More importantly, be sure to use a strong password (meaning: very random) and ...


9

Timing attacks against WPA TKIP have been successfull: http://www.itworld.com/security/57285/once-thought-safe-wpa-wi-fi-encryption-cracked Also curtusy of @Iszi Japanese researchers in 2009 published a paper saying that they had been able to decrypt WPA-TKIP traffic: http://pcworld.about.net/od/securit1/New-Attack-Cracks-Common-Wi-Fi.htm If you are using ...


9

PEAP is an authentication protocol which reuses TLS to establish a secure sort-of tunnel between the client and the authentication server. Nominally, SSL/TLS uses a bidirectional full-duplex transport medium (such as a TCP connection) and provides a bidirectional full-duplex tunnel. However, the initial parts of SSL/TLS (the "handshake") can be expressed as ...


9

WPA2 is more secure than WPA as explained by Terry. You just need to understand the difference between personal (pre shared key) and enterprise versions of both the protocols. The personal version is where all the users share a secret password that is configured in the access point. In the enterprise version there is a central authentication server and all ...


9

WPA2-Enterprise is (in my opinion) considerably more secure than PSK. Reasons WPA2-PSK has a single shared key amongst all devices. that means that if one of the devices is compromised the key is lost, so the more devices you have the risk of loss or compromise increases. As against this WPA2-Enterprise has per user secrets, so not the same problem. ...


8

The RSNA-CCMP filter is an accidental left-over from when I wrote the filtering system. It is exactly the same as the WPA2-CCMP filter. :D


8

I'm going to go out on a limb here and could be wrong, but... If there are two APs using the same encryption level and the same passphrase, then I believe most wireless clients will happily connect to either without raising a fuss. I do not believe that the equivalent of an SSH host key is used to fingerprint the original "authentic" AP. Therefore, if an ...


8

Pyrit upstream here. You start by eavesdropping the key exchange between the station and the access-point. The first packet (sent from the the AP to the STA) gives you the ANonce, the second packet (sent from the STA to the AP) gives you the SNonce. You can now guess a password, compute the Pairwise Master Key and construct the Pairwise Transient Key. ...


8

I'd look at OCLHashcat, as it let's you brute force with specific character sets and doesn't need to generate the list beforehand. I'm not sure what you mean by "incrementally" however, if you mean stopping and starting OHC will let you do that. In terms of cracking WPA2, you've got 3 options. Dictionary attacks Reaver attack against WPS (most ...


7

Yes, 16 characters is more than sufficient, if they are randomly generated using a cryptographic-strength PRNG. If you use lower-case, upper-case, and digits, and if you generate it truly randomly, then a 16-character password has 95 bits of entropy. That is more than sufficient. Actually, 12 characters is sufficient; that gives you 71 bits of entropy, ...


7

To decrypt a captured connection using WPA2, you must: Know the shared master key. Witness the target client's last synchronization / association attempt before the data you're looking at. WPA2 uses a key derivation method based on the shared PSK as described in RFC 4764 and your specific question is mentioned as a pitfall in section 8.10. Effectively, ...


7

Say you have 10 users. In PSK mode all 10 users are using the same passphrase to generate the same key. Therefore, the likelyhood of capturing traffic and analyzing it to find the key is higher with so much traffic, and that key will be good until all 10 users agree to change the passphrase (and therefore the key) If those same 10 users use their own ...


7

[...] if I am authorized to use a wireless network, and after authenticating myself I use something like wireshark or airopeek to sniff packets, how is this any different than just wardriving open wireless networks w/o authentication? Wardriving generically refers to the activity of identifying accessible access points. The term 'wardriving' is a play on ...


7

The situation you describe isn't really a concern. The WPA2 handshake never actually sends your password across; both the access point and the client send derived messages that demonstrate that they know the same password. So, spoofing a WPA2 access point won't help recover the password. However, it is possible to record the messages involved in a successful ...


7

The short answer is probably. The actual answer depends entirely on what "good enough" means to you. Do you need to disallow WiFi altogether? Perhaps you really need Ethernet cables run in pressure-monitored shielded conduit run under an access-controlled, video-monitored raised floor with locks on the exposed ports? Okay, that is overkill for almost ...


7

I would call this an evil twin attack. And it's not uncommon to see corporate laptops vulnerable to this. WPA2-Enterprise supports a number of EAPs - Extensible Authentication Protocols. (Wikipedia article) The security depends on which EAP you use, and how you configure it. Some EAPs more vulnerable to an "evil twin" attack than PSK, as an attacker doesn't ...


7

To answer your question, you really need to understand a little bit about how WPA2 works. To start with, both sides need a common starting point (the "Pairwise Master Key" or PMK) on which to build the encryption key ("Pairwise Transient Key" or PTK). This PMK is either the PSK for WPA2-PSK or it is generated by the RADIUS server during the EAP exchange ...


7

Changing the Default SSID would serve no particular security purpose where it's not entirely predictable (e.g. 'netgear'). It would allow you to easily identify your wireless network though, if there are lots of others about. It used to be the case where companies used one string for all their APs that it was relevant to Rainbow table generation (more ...



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