Attacks against SSL/TLS – BEAST/CRIME/BREACH

 (a) BEAST (Browser Exploit Against SSL/TLS)

  •  By Juliano Rizzo and Thai Duong, 2011 @ ekoparty Security Conference in Buenos Aires, Argentina
  •  Decrypts secure cookies against CBC mode (i.e AES or 3DES) in TLSv1

<References>
Demo and description: http://vnhacker.blogspot.com/2011/09/beast.html
Paper: http://packetstormsecurity.com/files/download/105499/Beast-SSL.rar/
Proof of Concept with javascript: http://erlend.oftedal.no/blog/beast/

(b) CRIME (Compression Ratio Info-leak Made Easy)

  • By Juliano Rizzo and Thai Duong, 2012 @ ekoparty Security Conference in Buenos Aires, Argentina
  • leverages compression side-channel, recovers the HTTP request headers
  • Injects partial chosen plaintext (CPA) into a victim’s requests + measures the size of encrypted traffic
  • HTTP-level compression: gzip (RFC 1952), defalte (RFC 1951)
  • Mitigated by disabling TLS/SPDY compression

<References>
1. Wiki: http://en.wikipedia.org/wiki/CRIME_(security_exploit)
2. Tor and BEAST: https://blog.torproject.org/blog/tor-and-beast-ssl-attack
3. Schneier’s Article: https://www.schneier.com/blog/archives/2011/09/man-in-the-midd_4.html
4. Generic attacks with compression: http://www.iacr.org/cryptodb/archive/2002/FSE/3091/3091.pdf

(c) BREACH (Browser Reconnaissance and Exfiltration via Adaptive Compression of Hypertext)

  • By Angelo Prado, Neal Harris, and Yoel Gluck, 2013 @ Blackhat 2013
  • CVE-2013-3587
  • leverages compression, takes advantage of HTTP responses
  • Mitigated by:Disabling HTTP compression
    – Separating secrets from user input
    – Randomizing secrets per request
    – Masking secrets (effectively randomizing by XORing with a random secret per request)
    – Protecting vulnerable pages with CSRF
    – Length hiding (by adding random number of bytes to the responses)
    – Rate-limiting the requests

<References>

1. Wiki: http://en.wikipedia.org/wiki/BREACH_(security_exploit)
2. Paper: http://breachattack.com/resources/BREACH%20-%20SSL,%20gone%20in%2030%20seconds.pdf
3. PPT: http://breachattack.com/resources/BREACH%20-%20BH%202013%20-%20PRESENTATION.pdf
4. Source Code: https://github.com/nealharris/BREACH