https://www.smacktls.com/#freak

"Among the various state machine problems we found, one is particularly
interesting because it leads to a server impersonation exploits against
several mainstream browsers (including Safari and OpenSSL-based browsers
on Android).

This attack targets a class of deliberately weak export cipher suites.
As the name implies, this class of algorithms have been introduced under
the pressure of US governments agencies to ensure that the NSA would be
able to decrypt all foreign encrypted communication, while stronger
algorithms were be banned from export (as they were classified as
weapons of war).

Support for these weak algorithms has remained in many implementations
such as OpenSSL, even though they are typically disabled by default;
however, we discovered that several implementations incorrectly allow
the message sequence of export ciphersuites to be used even if a
non-export ciphersuite was negotiated."

I commenti di:

Matthew Green:
http://blog.cryptographyengineering.com/2015/03/attack-of-week-freak-or-factoring-nsa.html

Ed Felten:
https://freedom-to-tinker.com/blog/felten/freak-attack-the-chickens-of-90s-crypto-restriction-come-home-to-roost/

rob
________________________________________________________
http://www.sikurezza.org - Italian Security Mailing List

Rispondere a