This Week in Security: Java’s Psychic Signatures, AWS Escape, And a Nasty Windows Bug

Java versions 15, 16, 17, and 18 (and maybe some older versions) have a big problem, ECDSA signature verification is totally broken. The story is a prime example of the …read more Continue reading This Week in Security: Java’s Psychic Signatures, AWS Escape, And a Nasty Windows Bug

How sensitive is the primary key stub of an ed25519 security key (~/.ssh/id_ed25519_sk)?

Now that OpenSSH supports Elliptic curve security keys (since version 8.2), it’s possible to generate a ed25519-sk key on a hardware security key:
$ ssh-keygen -t ed25519-sk -C comment

This generates a public and a private key parts. How … Continue reading How sensitive is the primary key stub of an ed25519 security key (~/.ssh/id_ed25519_sk)?

How do I turn an 88 byte ECDSA public key into a 65 byte uncompressed or 33 byte compressed key for use with bitcoin

In my situation my private key is in an HSM. I cannot access it for use with the various bitcoin golang libraries. Most of the functions require the private key "in-use". Although in my case, I can generate the signature later us… Continue reading How do I turn an 88 byte ECDSA public key into a 65 byte uncompressed or 33 byte compressed key for use with bitcoin