Personal highlights from 39c3
December 31, 2025 —
~wheresalice
Videos from all the #39c3 talks I attended are now online at media.ccc.de. There’s a huge number of videos here, and most of the talks I haven’t seen yet. But some personal highlights include:
- A Tale of Two Leaks: How Hackers Breached the Great Firewall of China
- Not an Impasse: Child Safety, Privacy, and Healing Together
- To sign or not to sign: Practical vulnerabilities in GPG & friends
- Excuse me, what precise time is It? (PTP Protocol)
- Hacking washing machines
- AI-generated content in Wikipedia - a tale of caution
- Agentic ProbLLMs: Exploiting AI Computer-Use and Coding Agents
- Persist, resist, stitch
- Variable Fonts — It Was Never About File Size (pushing the limits of what you can do with a font file)
- Recharge your batteries with us - an empowering journey through the energy transition
- CSS Clicker Training: Making games in a “styling” language
- Textiles 101: Fast Fiber Transform
- 51 Ways to Spell the Image Giraffe: The Hidden Politics of Token Languages in Generative AI
- The Small Packet of Bits That Can Save (or Destabilize) a City
- The Museum of Care: Open-Source Survival Kit Collection (news from the David Graeber institute)
- a media-almost-archaeology on data that is too dirty for “AI” (what scraped data do LLM trainers exclude)
- What Makes Bike-Sharing Work? Insights from 43 Million Kilometers of European Cycling Data
- Shit for Future: turning human shit into a climate solution
- Learning from South Korean Telco Breaches (turns out SSL downgrade attacks are still a thing)
- APT Down and the mystery of the burning data centers (on that South Korean government datacenter that burned down and the suspicious timing)
- The Spectrum - Hackspace Beyond Hacking (intro to a FLINTA* hackspace in Munich)
- How to keep Open Source open without leaving our communities open to threats (ongoing work to build crisis management in open source organisations)
- We, the EU, and 1064 Danes decided to look into YouTube: A story about how the EU gave us a law, 1064 Danes gave us their YouTube histories, and reality gave us a headache (on getting access to VLOPSEs data via GDPR / DSA as a researcher, in this case YouTube data)
But I’ve still got 60+ videos still to watch from the talks I didn’t attend
The people who attended in-person will probably tell you that the workshops, meetups, etc were more valuable than the talks. But they’re (mostly) not shared online
I had a great time joining remotely via the streams, Matrix and Mastodon. But I do miss the smaller Congress events of the Berlin era where it felt like a tighter-knit community
Let me know your favorites on mastodon
Tags: 39c3