Daniel John Debrunner <[EMAIL PROTECTED]> writes:

> Could you explain how having the hash makes a dictionary attack easy?

Cf for example http://en.wikipedia.org/wiki/Dictionary_attack:
  :
  However many systems store a hashed version of the password and make
  it available under certain circumstances, such as a
  challenge-response authentication exchange between two parties. If
  an attacker can obtain the hashed password, they can test guessed
  passwords rapidly, often at a rate of tens or hundreds of millions
  of guesses per second.
  :
Derby's algorithm is known, so there is no need to call 

   SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.user.<dummyuser>','<guess>')
   VALUES SYSCS_UTIL.SYSCS_GET_DATABASE_PROPERTY('derby.user.<dummyuser>')

to check the guess.  The attack could proceed off-line.

Of course, the dba can get at the hash value anyway by digging into the database
files..

Dag

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