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Passwords are the most
common form of authenticating today. Conservative
estimates show that there are close to a billion
password-based authentications per day.
Today, users must
remember too many identities and password combinations
at an ever increasing rate.
Some problems with
passwords include:
Access to user
passwords by system administrators - System
administrators who keep assigned passwords written down
for quick access when a user forgets their own
passwords. This destroys the whole element of
nonrepudiation.
Risk of undetected
theft - Passwords can be stolen without the
knowledge of the user. Similarly, a user can unknowingly
disclose a password through eavesdropping, persuasion,
posing as a system administrator, etc.... Loss of a
password can only be discovered by detecting its misuse
or finding it in the possession of an unauthorized user.
Risk of undetected
sharing - Passwords can be easily shared. Current
systems can create situations where a secretary will use
their boss's passwords to read e-mails. However, reading
the boss's e-mail should be possible without allowing
the secretary to send e-mail under the boss's identity.
A proxy implementation would allow secretaries to answer
their boss's e-mail while signing the replies with their
own names.
Risk of weakest link
- Users tend to repeat selecting the same password at
multiple sites. Exposure of a user password at a weak
site can lead to the users accounts being compromised at
other sites. Unfortunately, there is also no technical
way to prevent users from selecting the same passwords
at multiple sites.
Risk of guessing -
If a password can be guessed via personal knowledge,
tendencies and other easily obtainable information.
Risk of
dictionary/brute force attack - Passwords can be
exhaustively searched by utilizing a dictionary or brute
force attack to try every possible combination of
typeable letters.
Risk of password play
- If a password is transmitted from client to server or
even keyboard to terminal, it is possible to intercept
and record this information.
Risk of server
spoofing - Web sites and applications can copy the
look and feel for use as a decoy to establish confidence
and obtain passwords from a user.
Risk of password reuse
- The requirement to change passwords with some
frequency is understood but the frequency to do so it
not. Forcing users to change passwords more frequently
could actually lead to less security than more. |