Re: Atmel "secure" crypto co-processor series microprocessors (AT91SAM7XC) leaking keys, plus bonus DESFire hack

[Adam Laurie <adam () algroup co uk>]

On 11/02/13 09:11, Adam Laurie wrote:
> 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.

It has been pointed out that in fact the example code is not vulnerable 
due to a subtlety in variable declaration. I have amended the post to 
take this into account, and apologise for the mis-information. However, 
the point about lack of clarity on this issue still stands, and, as 
we've seen, the potential for error still exists.

> Full story here:
>
>
> http://oamajormal.blogspot.co.uk/2013/02/atmel-sam7xc-crypto-co-processor-key.html

cheers,
Adam
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