DEF CON 27 Recap: Trends, Topics, and Schedules

Table of Contents

1. Topics

  • AI
  • Application Security
  • Automobiles
  • Data brokers
  • Elections
  • Transportation
  • Windows

The following seems to have been less present this year when compared with previous years.

  • Blockchain
  • DDoS
  • IDS
  • Smart Contracts
  • Tor
  • Traffic construction
  • Unix
  • WiFi
  • Forensics
  • DNS
  • Pentesting
  • Botnets
  • Buffer overflows

2. Badge

Joe Grand (Kingpin) designed the official badge. NFMI (Near-Field Magnetic Induction) RF badge — the puzzle was social interaction, not classical cipher. Collect proximity contacts from 10 different badge types (Goon, Speaker, Vendor, Press, Village, Contest, Artist, CFP, Uber).

Badge firmware: Jackp0t — spoofs all badge types via firmware hack to auto-complete the quest (and rickroll nearby badges). Badge archive: media.defcon.org (1.3 GiB).

2.1. EFF T-Shirt Puzzle (5-Stage Pipeline)

The crypto puzzle at DC27 was on the EFF T-shirt, not the badge. Five-stage decode pipeline:

Stage Encoding Output
1 Morse code on shirt screen URL (eff.org/shr)
2 Knitting chart steganography → Morse "wander"
3 Braille Unicode steganography → ASCII "cephalopod"
4 Planetary alignment (Chinese Remainder Theorem) "taboo"
5 One-time pad, key = "wandercephalopodtaboo" "seeyouspacecowboy"

See EFF's DC27 T-Shirt Puzzle writeup.

Stages 1–3 involve steganography (domain-crossing transforms, like the Aphex Twin spectrogram). Stage 4 is number theory. Stage 5 (OTP) is a bijection given the key — the same key-dependent reversibility as Janus and keyed ciphers.

3. Schedule

3.2. Don’t Red-Team AI Like a Chump

Ariel Herbert-Voss

3.4. Change the World, cDc Style: Cowtips from the first 35 years

Joseph Menn, Peiter Mudge Zatko, Chris Dildog Rioux, Deth Vegetable, Omega

4. Villages

There are several new villages that were present at 27 that reflect the expanding technology landscape.

4.1. AI

4.2. AppSec

5. Media

6. Schedules