Simon Willison’s Weblog

hash_ring 1.2. A Python library for consistent hashing with memcached, using MD5 and the same algorithm as libketama. Exposes an interface that is identical to regular memcache making this a drop-in replacement.

# 5th May 2009, 1:45 pm / amirsalihefendic, caching, consistenthashing, django, hashring, libketama, md5, memcached, python

Researchers Show How to Forge Site Certificates. Use an MD5 collision to create two certificates with the same hash, one for a domain you own and another for amazon.com. Get Equifax CA to sign your domain’s certificate using the outdated “MD5 with RSA” signing method. Copy that signature on to your home-made amazon.com certificate to create a fake certificate for Amazon that will be accepted by any browser.

# 30th December 2008, 3:27 pm / collisions, edfelten, equifaxca, hashes, md5, security, ssl

Hash Collisions (The Poisoned Message Attack). Demonstrates the MD5 weakness by providing two deliberately engineered PostScript documents with the same MD5 hash but radically different rendered output.

# 4th April 2008, 7:24 pm / collisions, hashing, md5, postscript, security

In rainbows. Dopplr generates a unique colour for each city using an MD5 hash. The colours are then used in subtle but intelligent ways throughout the design—right down to the favicon.

# 23rd October 2007, 10:39 pm / colour, design, dopplr, favicon, hashing, matt-biddulph, matt-jones, md5