Although several parts of Tor have been redesigned and upgraded over many years, the algorithm for the HashedControlPassword still remained the same.
It still uses SHA-1 as the basis of the OpenPGP S2K algorithm, despite the fact that the algorithm has long-since been obsolete by newer and better hashing algorithms (on top of it, has had some practical collision attacks[1]). This is made worse by the fact that the S2K algorithm is not iterative (in the sense of recursive hashing), but rather repeats the salt+password many times in the hash digest until it reaches a certain amount of bytes. Theoretically, an attacker can expose this to autheticate into a Tor Control Port without having to know the password. Are there any plans to revamp the algorithm for newer Tor versions? [1]: https://shattered.io/ _______________________________________________ tor-dev mailing list -- [email protected] To unsubscribe send an email to [email protected]
