https://schaerli.org Hi, I'm Pascal. A cyber security master's graduate from ETH Zürich, now a dedicated Cryptography Engineer with a strong passion for coding and scripting. en-us Thu, 05 Nov 2026 21:57:34 GMT https://schaerli.org/briefs/signal-key-transparency/ Signal Messenger just added Key Transparency (KT) for automatic key verification. It's good but a bit timid. I'm comparing their KT with the one used by Proton, where I disclosed some weaknesses earlier this year. Mon, 17 Aug 2026 15:22:45 GMT https://schaerli.org/briefs/signal-key-transparency/ https://schaerli.org/briefs/q-day-timeline/ The Post-Quantum cryptography timeline of industry leaders just went from "we have a decade" to "we have 33 months." Both Google and Cloudflare are now targeting 2029 for full post-quantum security, including authentication, not just encryption. Tue, 07 Apr 2026 19:53:43 GMT https://schaerli.org/briefs/q-day-timeline/ https://schaerli.org/briefs/merkle-tree-certificates/ X.509 certificates have run the web for three decades. Quantum computers might be what finally kills them. Google announces they don't have immediate plans to add support for post-quantum secure X.509 certificates in Chrome in favor of a newer standard. Fri, 27 Feb 2026 21:47:49 GMT https://schaerli.org/briefs/merkle-tree-certificates/ https://schaerli.org/briefs/when-giant-use-toothpicks/ Fireblocks is a digital asset custody platform, protecting trillions of dollars. During a security review at work I found how they protect their 4096-bit RSA 'disaster recovery' keys for customers with 2 rounds of MD5. Thu, 03 Jul 2025 20:50:38 GMT https://schaerli.org/briefs/when-giant-use-toothpicks/ https://schaerli.org/briefs/eth-study-materials/ Welcome to my collection of ETH Zürich study materials. As a former tutor at ETH, I've created resources for two Computer Science courses in the Electrical Engineering and Mechanical Engineering bachelor programs. Tue, 01 Dec 2020 23:00:32 GMT https://schaerli.org/briefs/eth-study-materials/