padding attack vs. PKCS7

[travis+ml-cryptography at subspacefield.org]

http://www.matasano.com/log/1749/typing-the-letters-a-e-s-into-your-code-youre-doing-it-wrong/

Towards the end of this rather offbeat blog post they describe a
rather clever attack which is possible when the application provides
error messages (i.e. is an error oracle) for PKCS7 padding in e.g. AES
CBC-encrypted web authenticators that allows an adversary to attack
the crypto one octet at a time.
-- 
Obama Nation | My emails do not have attachments; it's a digital signature
that your mail program doesn't understand. | http://www.subspacefield.org/~travis/ 
If you are a spammer, please email john at subspacefield.org to get blacklisted.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://www.metzdowd.com/pipermail/cryptography/attachments/20090611/f118f17c/attachment.pgp>