<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Passwords on Signal &amp; Syntax</title><link>https://signal-and-syntax.com/tags/passwords/</link><description>Recent content in Passwords on Signal &amp; Syntax</description><generator>Hugo</generator><language>en-us</language><lastBuildDate>Mon, 17 Nov 2025 06:00:00 -0700</lastBuildDate><atom:link href="https://signal-and-syntax.com/tags/passwords/index.xml" rel="self" type="application/rss+xml"/><item><title>Hash Collisions: Why Your 'Unique' Fingerprints Aren't (And Why That's Usually OK)</title><link>https://signal-and-syntax.com/posts/hash-collisions/</link><pubDate>Mon, 17 Nov 2025 06:00:00 -0700</pubDate><guid>https://signal-and-syntax.com/posts/hash-collisions/</guid><description>In 2017, Google researchers generated two different PDF files with identical SHA-1 hashes, finally proving what cryptographers had warned about for years: hash functions don&amp;rsquo;t create truly unique fingerprints ( Stevens et al., 2017 ). This &amp;ldquo;SHAttered&amp;rdquo; attack required 9 quintillion SHA-1 computations, which is the equivalent to 6,500 years of single-CPU computation. The attack cost approximately $45,000 in cloud computing resources, making it accessible to well-funded adversaries but not casual attackers.</description></item></channel></rss>