Yep, such passwords are a VERY bad idea...  LC4 can ferret these type of
substitutions out faster than you can blink (relatively speaking).

May I suggest a different approach to creating a strong password, one that
doesn't need to be written down or require a struggle to memorise a string
of hieroglyphics.

Take a phrase or sentence of around 10-15 words in length, one that you can
easily recall.  Here's one lifted at random from an article I was reading:
"Of course, not everyone likes to read their email while they're on
holiday."  Now, take the first letter of each word, (or maybe two from
certain words, I'll use two letters and the ' from the word 'they're' in
this example) and any punctuation marks can be included as well.  Now we
have "Oc,neltrtewt'roh."  Mangle it a little more by converting some letters
to numbers, capitalising certain letters, (I suggest based on emphasis, to
make them easier to remember), maybe toss in another symbol or two, whatever
you like.  In the above example this gives us "0c,nEl2rt3wt'Roh."  Note that
the leading 'O' has changed to numeric zero.  This gives us 17 random chars,
symbols, numbers, upper and lower case, all the elements of a good, secure
password, and will take so long to brute-force that your data will be beyond
its use-by date, or you'll have changed passwords long before it can be
broken.

After you've done this a couple of times, you'll find that you can create
strong passwords on-the-fly, and never need to write them down.  They are
also MUCH easier to commit to memory.

The following article is well worth a read also.  "Choosing Strong
Passwords" at http://online.securityfocus.com/infocus/1319

One small point from the article; LC (and most other password crackers, so
far as I know) is not able to cope with non-printable characters.  So, to
make a password that cannot even be brute-forced, include at least one
non-printing character in your password, as follows:

<quote>
To really increase password strength, use a non-printable ascii character
within the first seven characters. ie. within the password 'secret' embed an
alt character secret where you hold down the ALT key while pressing the 1,2,
and 9 keys on the numeric keypad. NOTE: for laptop users, you'll have to
activate numlock and use the j,k,l,u,i,o keys that correspond to the numeric
keypad.
</quote>


Garryck


-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
Sent: Thursday, 27 June 2002 7:41 AM

>
> Plug in an easily remembered word and it spits out an 1337 version
> containing caps, lower-case, numbers, and non-alphanumeric characters.

NOOOOO!!!!

Surely it's obvious why this would be a BAD password. It's based on a
dictionary word, with simple, common letter substitutions. This is the
only the next step up (common permutations) from a plain dictionary
attack. If you're going to use "h4<Km3" as a password, expect to get
hacked.

Don't base your passwords on dictionary words, phonetic misspellings,
names, slang, etc. They're all well-known. Use something properly random;
I usually do a 'strings -8 /dev/urandom' and then pick something from the
first screenful that I think I can memorise. I know people advise never to
write down passwords, but I do and keep it down the back of my cellphone
for the week or so it takes me to memorise it. IMHO that's still a LOT
safer than having an easily-cracked password. But DON'T write it down on
a post-it note behind your monitor or under the keyboard!!




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