S 2.

>    This document does not consider AES-CBC ([RFC3602])as AES-CBC
>>    requires the IV to be unpredictable.  Deriving it directly from the
>>    packet counter as described below is insecure.
>>
>> Can you provide a cite for this?
>>
>>
>> Even RFC 3602 requires that the IV be randomly generated (and for good
>> measure requires that it be unpredictable)
>>
>
> That's just a cite to a requirement, not to it being insecure. Do you have
> a citation to the relevant threat?
>

Predictable IV can be exploited by chosen plain text attacks. RFC3602 cites
[CRYPTO-B] in teh sceurity consideration section:
"""

For more information regarding the necessary use of random IV values,
see [CRYPTO-B <https://tools.ietf.org/html/rfc3602#ref-CRYPTO-B>].

"""
with :

[CRYPTO-B]   Bellovin, S., "Probable Plaintext Cryptanalysis of the
             IP Security Protocols", Proceedings of the Symposium on
             Network and Distributed System Security, San Diego, CA,
             pp. 155-160, February 1997.
             http://www.research.att.com/~smb/papers/probtxt.pdf

This links works:
https://www.cs.columbia.edu/~smb/papers/probtxt.pdf
_______________________________________________
IPsec mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/ipsec

Reply via email to