Simon Willison’s Weblog

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.

Posted 4th April 2008 at 7:24 pm

Recent articles

Useful patterns for building HTML tools - 10th December 2025
Under the hood of Canada Spends with Brendan Samek - 9th December 2025
Highlights from my appearance on the Data Renegades podcast with CL Kao and Dori Wilson - 26th November 2025

collisions 2 hashing 12 md5 4 postscript 1 security 569

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