A researcher has devised a method that reduces the time and
resources required to crack passwords that are protected by the
SHA1 cryptographic algorithm. The optimization, presented on
Tuesday at the Passwords^12 conference in Oslo, Norway, can
speed up password cracking by 21 percent. The optimization works
by reducing the number of steps required to calculate SHA1
hashes, which are used to cryptographically represent strings of
text so passwords aren't stored as plain text. Such one-way
hashes—for example 5baa61e4c9b93f3f0682250b6cf8331b7ee68fd8 to
represent "password" (minus the quotes) and
e38ad214943daad1d64c102faec29de4afe9da3d for "password1"—can't
be mathematically unscrambled, so the only way to reverse one is
to run plaintext guesses through the same cryptographic function
until an identical hash is generated. Jens Steube—who is better
known as Atom, as the pseudonymous developer of the popular
Hashcat password-recovery program—figured out a way to remove
identical computations that are performed mu