1. TLS/SSL Renegotiation Vulnerability Thai N. Duong [email_address]

2. Agenda

SSL/TLS protocol

SSL/TLS renegotiation vulnerability

Q & A

3. About me

CISO at DongA Bank

Blogger -http://vnhacker.blogspot.com

Administrator http://www.hvaonline.net

Member Team CLGT -http://vnsecurity.net

Bug Hunter Yahoo!, Oracle/SUN, Apache Foundation, etc.

4. Copyright notice

Most of subsequent slides are copied from elsewhere on the Internet

You should be careful if you want to reuse them

This compilation is in public domain

5. 6. 7. 8. 9. DHE -RSA-AES256-SHA 10. DHE - RSA -AES256-SHA 11. DHE - RSA - AES256 -SHA 12. DHE - RSA - AES256 - SHA 13. Renegotiation vulnerability

Active MITM attacker

Inject an arbitrary amount of chosen plaintext into the beginning of the application protocol stream

Execute a HTTP transaction, authenticated by a legitimate user

14. 15. 16. 17. 18. Trigger renegotiation

Client certificate authentication

Differing server cryptographic requirements

Client-initiated renegotiation

19. 20. Reference

http://clicky.me/tlsvuln

http://extendedsubset.com/Renegotiating_TLS.pdf

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-3555

21. Thank you! Question?