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Information Security

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  • HSM certainly can be configured to require authentication per use, but these keys are "administrative keys" in a sense. Indeed these admin keys (as well as HSM root keys) are very secure, but I don't care about HSM's keys. I care about my application keys like TLS certificates, which is of course operating unattended. Commented 2 days ago
  • @user1641237: I am talking about your keys. Even if an attacker is standing right in front of the HSM, they cannot simply use your TLS keys (unless you somehow assume that you've badly screwed up the configuration). They need to (1) steal the credentials from the target application to impersonate that application towards the HSM, (2) stay physically present to use the key, (3) not try to trigger any intrusion detection, and (4) accept any limitations enforced by the HSM (like rate limits). Do you not see how much more difficult this is compared to copying the key from some server storage? Commented 2 days ago
  • @user1641237: This seems a bit like the question why we need to protect password hashes in the application backend when attackers can just try out passwords in the frontend. Because an online attack is slow, “loud” and can be stopped at any time once detected. In comparison, if the attacker walks away with the hashes, they have all the time in the world to quietly break them offline. One way to protect the hashes is in fact an HSM. Commented 2 days ago
  • I get that they need to authenticate to the HSM, but won't a separate, cheap $500 box programmed to enforce the limit (over a local network link) do the same? We are talking about Very Expensive (TM) hardware anti-tamper measures here... These features do not matter for any "remote attacker" talking through the command interface. Commented yesterday
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    @user1641237: Maybe the issue here is the term “tamper-proof”. HSMs aren't just difficult to break into – this could be implemented in all kinds of ways and doesn't require sophisticated hardware. They actively destroy the keys when tampering is detected. Commented yesterday