Scalar reveals the secret value about cheetah HOT 5 CLOSED

Hi! This is indeed an expected behavior for types that implement the Copy trait, for which dropping the value won't zeroize the original memory.

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So, clearing the original memory doesn't matter because STARKs don't have a trapdoor?

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I am not sure to understand your sentence.
This library is intended to provide a mid-level API of elliptic curve operations over a specific curve. If you intend to use it (which I don't recommend by the way as it is unmaintained, unless it is for academic/educative purposes), in a context where Scalar values have to remain secret, you can use a wrapper that doesn't implement Copy, and will properly wipe-out memory on drop.

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I am not sure to understand your sentence.
This library is intended to provide a mid-level API of elliptic curve operations over a specific curve. If you intend to use it (which I don't recommend by the way as it is unmaintained, unless it is for academic/educative purposes), in a context where Scalar values have to remain secret, you can use a wrapper that doesn't implement Copy, and will properly wipe-out memory on drop.

As the description says that Cheetah is STARK friendly, I am just saying STARK has no trapdoor unlike traditional Cryptography which has a trapdoor in keys, signatures, etc. So, Scalar implements the Copy trait.

Yeah, if someone prefers to use Scalar as a secret, they can wrap the limb array with Box. But, this must be mentioned somewhere.

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The zeroize crate is already fairly well documented on what guarantees it provides and which situations that may leave unwanted copies of your data in memory. If you want to use a higher-level abstraction, you can use the secrecy crate. Again, while you mention STARKs, this library is solely intended to provide on its own support for elliptic curve operations over the so-called Cheetah curve. It is not the purpose of this library, or any library for what it's worth, to describe the behavior of all its internal dependencies.

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