Simon Willison’s Weblog

4th April 2008 - Link Blog

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

Live blog: Code w/ Claude 2026 - 6th May 2026
Vibe coding and agentic engineering are getting closer than I'd like - 6th May 2026
LLM 0.32a0 is a major backwards-compatible refactor - 29th April 2026

This is a link post by Simon Willison, posted on 4th April 2008.

collisions 2 hashing 12 md5 4 postscript 1 security 600

Monthly briefing

Sponsor me for $10/month and get a curated email digest of the month's most important LLM developments.

Pay me to send you less!

Sponsor & subscribe