The Atmel AT91SAM7XC series of microprocessors contain a crypto
co-processor which is DES and AES capable. They include a write-only
memory for key storage and multiple physical security measures to
prevent decapping etc.
However, due to poor memory management, in certain circumstances it is
possible to recover the crypto keys from a live system via the standard
JTAG programming interface. These circumstances are made more likely to
exist in the wild by the fact that the example software provided by
Atmel is itself vulnerable.
Full story here:
http://oamajormal.blogspot.co.uk/2013/02/atmel-sam7xc-crypto-co-processor-key.html
The potential for this to be an issue has been raised within the Atmel
support community several times over the years, dating back to at least
2006. I personally raised it with them in 2011.
However, I am not aware of any clarification being issued by Atmel, nor
of any definitive proof one way or the other being made public until now.
The NXP DESFire 'hack' is purely a result of the weakness in the
AT91SAM7XC, and nothing to do with DESFire itself, but demonstrates why
this is a real problem. I'm sorry they got in the firing line, but they
were just in the wrong place at the wrong time... (cyber)war is heck!
cheers,
Adam
--
Adam Laurie Tel: +44 (0) 20 7993 2690
Suite 117 Fax: +44 (0) 20 7691 7776
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Surrey mailto:adam@algroup.co.uk
KT6 4JX http://rfidiot.org