[CLUE-Tech] WEP security?

[David Anselmi]

Tom Poindexter wrote:
[...]
> 
> 40-bit WEP can probably be cracked in under 30 seconds for most cases, where
> WEP keys are choosen from ASCII characters.  Using ASCII keys are easy to
> type, but essentially reduces the key space from 40 bits to about 21 bits.
> A full brute force on 40 bits might take several weeks, but due to other
> problems in WEP (weak keys, etc.) that time is probably a matter of days.
> 
> 104 bit WEP is harder to brute force, but taking advantage of WEP 
> problems and a small cluster of machines, a week should be considered the
> time to break a 104 bit WEP key.

Brute force is unnecessary for WEP.  There is a flaw in the crypto that 
allows breaking the key regardless of length.  All that's required is to 
sniff 5-6M packets which takes "several hours on a moderately loaded 
network".  Sean's message had a link to the paper.

So WEP is in the same category as cleartext passwords.  It adds a little 
difficulty to cracking, but won't stop anyone serious.

It would be interesting to see a howto or have a talk on setting up a 
VPN to prevent unauthorized use of a wireless LAN.

Dave