A dead man’s full-yet-responsible-disclosure system

Presented at DEF CON 30 (2022), Aug. 12, 2022, 4:30 p.m. (45 minutes)

Do you ever worry about responsible disclosure because they could instead exploit the time-to-patch to find you and remove you from the equation? Dead man switches exist for a reason... In this talk we present a new form of vulnerability disclosure relying on timelock encryption of content: where you encrypt a message that cannot be decrypted until a given (future) time. This notion of timelock encryption first surfaced on the Cypherpunks mailing list in 1993 by the crypto-anarchist founder, Tim May, and to date while there have been numerous attempts to tackle it, none have been deployed at scale, nor made available to be used in any useful way. This changes today: we’re releasing a free, open-source tool that achieves this goal with proper security guarantees. We rely on threshold cryptography and decentralization of trust to exploit the existing League of Entropy (that is running a distributed, public, verifiable randomness beacon network) in order to do so. We will first cover what all of these means, we will then see how these building blocks allow us to deploy a responsible disclosure system that guarantees that your report will be fully disclosed after the time-to-patch has elapsed. This system works without any further input from you, unlike the usual Twitter SHA256 commitments to a file on your computer.

Presenters:

• Yolan Romailler - Applied Cryptographer
  Yolan is an applied cryptographer delving into (and mostly dwelling on) cryptography, secure coding, and other fun things. He has previously spoken at Black Hat USA, BSidesLV, Cryptovillage, NorthSec, GopherConEU and DEF CON on topics including automation in cryptography, public keys vulnerabilities, elliptic curves, post-quantum cryptography, functional encryption, open source security, and more! He notably introduced the first practical fault attack against the EdDSA signature scheme, and orchestrated the full-disclosure with code of the CurveBall vulnerability.

Links:

• https://forum.defcon.org/node/242203
• https://infocon.org/cons/DEF CON/DEF CON 30/DEF CON 30 video and slides/DEF CON 30 - Yolan Romailler - A Dead Man’s Full-Yet-Responsible-Disclosure System.mp4
• https://infocon.org/cons/DEF CON/DEF CON 30/DEF CON 30 video and slides/DEF CON 30 - Yolan Romailler - A Dead Man’s Full-Yet-Responsible-Disclosure System.srt (subtitles)
• https://www.youtube.com/watch?v=IW7sdSd2wOQ

Similar Presentations:

• Still Hacking Anyway (SHA2017) / Developments in Coordinated Vulnerability Disclosure: The government is here to help
• 30C3 (2013) / Disclosure DOs, Disclosure DON'Ts: Pragmatic Advice for Security Researchers
• DEF CON 10 (2002) / Disclosure: The Mother of All Vulnerabilities