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WPA3   (added Aug. 3, 2018)

As of July 2018, it is too early to walk about WPA version 3 (WPA3) with any authority. No one has yet kicked the tires on the protocol and it is not clear when devices will even support it. Anything that supports WPA3 should also support WPA2, so there won't be a big bang conversion.

The biggest flaw with WPA2, is that bad guys can make off-line brute force guesses of the Wi-Fi password. Billions and billions of guesses every second. WPA3 should eliminate this flaw. That said, a sufficiently long WPA2 password (over 16? characters) also eliminates the problem.

Here is an overview of the improvements. Most of this information comes form the Information Assurance website of the NSA, specifically a June 2018 report called WPA3 will Enhance Wi-Fi Security.

The improvements are scheduled in two phases, the first is known as WPA2 enhancements and it is expected to be released before the end of 2018. The second phase is full blown WPA3. WPA3 compliant products are expected to start appearing before the end of 2018. The WPA2 enhancements mandate the use of Protected Management Frames (PMF), more stringent validation of vendor security implementations, and improved consistency in network security configuration.

IEEE 802.11w, the standard that describes PMF, was ratified in 2009 becomes mandatory. Without it, management frames are transmitted unencrypted and their integrity is not verified. PMF ensures integrity of network management traffic, provides protection against eavesdropping, replay and the forging of management action frames. This protects against DoS attacks that use forged deauthentication/disassociation frames to kick clients off a network and force them to authenticate again.

Many wireless vulnerabilities are the result of poor implementation or misconfiguration. WPA2 enhancements will require additional tests on Wi-Fi certified devices to ensure both the use of best practices and that the products yield expected behaviors. The WPA2 enhancement also defines a set of secure cipher suites to prevent an attacker from exploiting a configuration weakness.

Currently Wi-Fi networks can be completely open, no password needed, no encryption used. This will no longer be possible with WPA3 which introduces Opportunistic Wireless Encryption (OWE). OWE provides individualized data encryption to Wi-Fi clients using public open networks. No more eavesdropping. The encryption process is transparent to users. They see and join the Wi-Fi network as they would an Open network. BIG improvement. Technically, OWE uses an unauthenticated Diffie-Hellman key exchange during association, resulting in a Pairwise Master Key (PMK) used to derive the session keys.

Another huge improvement was mentioned above, resistance to brute force password guessing. The WPA2 Pre-Shared Key (PSK) mode is gone, replaced by the WPA3 Simultaneous Authentication of Equals (SAE). SAE limits the number of guesses an attacker can make. The user experience does not change with SAE, people still enter a password, just as they do now with WPA2-PSK.

Finally, WPS is being replaced with DPP (Device Provisioning Protocol). As with WPS, DPP aims to be a simple way for devices without a screen or keyboard to join a Wi-Fi network. I am skeptical; anything that tries to be user friendly is likely to not be secure. We'll see how this plays out. As some devices require WPS, it can not be killed off completely. Like WPS, DPP introduces new terminology, a configurator and an enrollee.

The configurator will be a smart phone or tablet that is already part of the network and can provision new devices. How it gets the ability to provision new devices is not clear. How it loses the ability once it is lost or stolen is also not clear. WPS had 4 or 5 different modes of operation and so too does DPP. Devices can be granted access to the network by scanning a QR code, negotiation of a trusted public key using a passphrase/code, NFC, or Bluetooth. Ugh.

Wi-Fi devices have utilized AES with 128 bit keys for data protection for some time. WPA3 will mandate 256-bit encryption and use of CNSA approved cipher suites.

WiFi Over-The-Air Encryption: WEP, WPA and WPA2

At first, you might be thinking what more is there to say about WiFi encryption? The basic rules have not changed in a long time and can be boiled down to USE WPA2. But, there is more to it.

Introduction: WiFi supports three different schemes for over-the-air encryption: WEP, WPA and WPA2 (WPA version 2). All of the options encrypt data traveling between a WiFi device and the router or Access Point (AP) that is the source of the wireless network. Once data leaves the router, bound for the Internet at large, WEP, WPA and WPA2 are no longer involved.

As noted everywhere, WPA2 is the best option. However, WPA2 is not a simple On/Off checkbox, there are further options. These additional options are TKIP, AES or CCMP. Do not choose TKIP. Doing so, means you are, in effect, using the less-secure WPA encryption. AES and CCMP are two names for the same thing. Whichever your router uses, chose it.

And, some routers may not offer just WPA2. I have seen routers that only offered a combination of either WPA or WPA2. Stand-alone or exclusive WPA2 is more secure.

For more on the three types of encryption see Wi-Fi Security: Should You Use WPA2-AES, WPA2-TKIP, or Both? by Chris Hoffman (December 2014).

Wi-Fi Passwords

And, you are still not done. WPA2-AES (the same as WPA2-CCMP) can still offer poor security if the password is too short. Nothing can be done to prevent an attacker from capturing network traffic and using a brute force attack to decrypt it off-line, making billions of guesses a second.

Just how many billions of guesses per second? According to Paul Moore (Passwords: Using 3 Random Words Is A Really Bad Idea! October 2017) it varies based on the hashing algorithm. A computationally expensive algorithm, SHA512, slows things down to 8 billion a second. If a password is encrypted with SHA256, then we can expect 23 billion guesses/second, with SHA1 expect 70 billion/second. The fastest, and thus least secure, algorithm is MD5. Moore says MD5 is still very common and it can be brute-forced at the rate of 200 billion guesses/second.

The shortest password allowed with WPA2 is 8 characters long. A password of 14 or 15 characters should be long enough to defeat most brute force guessing. WPA2 passwords can be up to 63 characters long. Of course, it is better to include both upper and lower case letters along with numbers. WPA2 passwords can also contain a host of special characters.

But wait, there's more.

A long password can still be guessed with a dictionary attack. Despite the name, this type of attack can include many passwords that are not words in the dictionary. Things like "Denver2013" or "I like MickeyMouse". Many websites have been breached over the years and bad guys can find massive databases of passwords that people have actually chosen. Thus, defending against a thorough dictionary attack means not using a password that any other human has used before. A tall order indeed, but not impossible.

For advice on choosing a globally unique password, see my November 2014 blog: Wi-Fi security vs. government spies.

To get a feel for how bad guys crack Wi-Fi passwords, see How I cracked my neighbors WiFi password without breaking a sweat by Dan Goodin (August 2012). One eight-character password was hard to guess because it was a lower-case letter, followed two numbers, followed by five more lower-case letters with no discernible pattern. That is, it didn't spell any word either forwards or backwards. Resisting the temptation to use a human-readable word made guessing much harder. I suspect having the numbers in the middle also made it harder, as most people don't do this. Still, even back in 2012, guessing every possible 8-character password was a do-able thing. Goodin suggests using four or five randomly selected words - "applesmithtrashcancarradar" for instance - to make a password that can be easily spoken yet prohibitively hard to crack. I would add a number and an upper case letter.

Some routers ship with default Wi-Fi passwords that look like they were randomly chosen. Do not trust this. Pick a new password. For more on this, see Scrutinizing WPA2 Password Generating Algorithms in Wireless Routers August 2015

In April 2018 the Boston Red Sox were caught using "baseball" as the Wi-Fi password in the visitors clubhouse at Fenway Park. I wrote about this on the Routers in the news page and commented on the strength of assorted new suggested passwords.

Old Devices

If you have an old device that is capable of WPA encryption but not the more recent WPA2 variety, then create a new network on the router that uses WPA encryption and chose an extra long password for it. If possible, this should be a guest network that is isolated from the private network.

If you have an old device that is not capable of either WPA or WPA2 encryption (that is, all it can do is WEP), get rid of it. WEP should not be used.

New Devices

A March 2017 article in PC Magazine, The Best Wi-Fi Mesh Network Systems of 2017 starts with a feature overview of nine different mesh systems. The most secure devices only offer WPA2: Plume, Eero, Securifi Almond 3 and Google Wifi. Two devices, Luma and Ubiquiti Amplifi offer both WPA and WPA2. In the "what were they thinking" category are devices that still offer WEP: Netgear Orbi, Linksys Velop and Amped Wireless Ally Plus.

Bad WiFi Passwords

  kyPeQ3!khx     (Too short and can't remember it)

  Dandelion     (Never use a word in the dictionary)

  Denver2012     (It is likely that someone else has used this before)

  DBF9fkhu28FF!ca4$cc5C1795ecc     (can't remember it)

Good WiFi Passwords - Long and Easy to Remember

  Yankee fan?     22New22York22Yankees22

  Like red tulips?     red123TULIPS123

  Like Shakespeare?     tobeornottobe-->THATisthe?

  From New York City?     new-yawk-RULES!!!!

  Like XKCD comics?     BatteryHorseStaple.etcetcetc

  Like to remember a date/place?     Denver///2012///

  Like your iPhone?     iOSiscoolerthanandroidhaha

  Like math?     6====ahalfdozen

  Like golf?     Icandriveagolfball300inches

  Like being a smartass?     >>>>>>>>thisismypassWORD

This page was last updated: August 3, 2018 7PM CT     
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