Popular Security Algorithm Compromised  By Michael Hall | Feb
17, 2005 | Print this Page  Cryptographic expert Bruce Schneier
has reported that the SHA-1 hashing algorithm (define) , upon
which several major applications such as SSL (define) and PGP
(define) depend for secure digital signing, has been broken.
While the computing resources needed to defeat the protection
SHA-1 provides remain impressive and out of the reach of most,
the discovery set a few experts back, including a security
technology group manager at the National Institute of Standards
and Technology (NIST) who as recently as last week declared
SHA-1 secure for the foreseeable future.  SHA-1 is used to
generate digital signatures. By processing a message or file
with SHA-1, applications produce a hashed version of the data
called a digest file. The hash, or digest, is much smaller than
the original file. In theory, the hashes from no two signed
files should ever be the same, meaning a file or message that's
been tampered with will yield a di