PEP 458: Secure PyPI downloads with package signing

I still think this statement is vastly overstating what the PEP addresses.

  • legitimately published yet malicious packages are not in any way prevented or identified by this proposal
  • a compromise of PyPI’s storage system is the only compromise that would be protected against, assuming none of the keys were kept in compromised storage
  • there’s no recovery from a compromise of the root key
  • recovery implies restoration, as Paul mentioned, but all we can really do is fail validation for anything signed by a key that was never properly endorsed or that was (presumably compromised and) used after its expiration
  • (I assume that there’s no attack whereby the attacker forces a key rotation and resigning of a package that was injected without correctly signed metadata, but I haven’t worked this one through)

MITM attacks and client-side redirection attacks seem to be the primary vector being protected against. They should at least get a mention.

I’m not aware of anyone at Microsoft using TUF in production. Could you email me at steve(dot)dower(at)microsoft.com with either the team or a person you know who is involved? My understanding was that TUF does not meet our compliance requirements, so I’m interested to see how they made it work.

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