miTLS Reports Exploitable Weakness in TLS implementations

[Bob Gezelter]

miTLS, a joint project between Inria and Microsoft Research has reported a series of exploitable weaknesses in the state machines used to implement TLS. Among others, Apples iOS and Google's Android, as well as other software products (e.g., Safari) including TLS implementations on other platforms.

In short, the weakness allows an attacker to force the use of "export-level" keys, even when not requested. The code proceeds to accept the request. These keys can then be broken, compromising the entire TLS session, as well as future server (emphasis, SERVER) sessions using the same underlying private key.

A more complete description of this and several similar TLS state machine attacks is at:
https://www.smacktls.com/

According to the article at smacktls.com, a more complete paper describing these weaknesses is in preparation for publication.

- Bob Gezelter, http://www.rlgsc.com