3 ms·
It authenticates the domain of the sender, right?
by alexchamberlain 14y ago
It authenticates the domain of the sender, right?
- tptacek 14y agoIf you want to impute that much authority to it, sure, but the actual signature verification depends on the insecure DNS anyways. Do not make security decisions based on DKIM. It's an anti-spam mechanism and that's all.
- alexchamberlain 14y agoMy personal opinion is that all email should be considered from a random person.
- tptacek 14y agoI tend to agree, and further suggest that DKIM shouldn't really change that calculation.
- jrabone 14y agoCurious - does DNSSEC add much to the amount of trust one can assign to DKIM verification? Or are there better solutions (both for trusted DNS and DKIM-alike)?
- tptacek 14y agoThe limitations of DKIM are bigger than the fact that it relies on DNS. The bigger challenge is that domain names are not a particularly valuable trust boundary. Applications on the Internet are full of bugs that allow attackers to source messages from other domains. DNSSEC is a boondoggle, and so far as I know no popular application on the entire Internet relies on it for security. But we don't need to hash out DNSSEC vs. DNS to see why a cracked DKIM key isn't a major Internet security hole.
- Evbn 14y agoHow does that signature verification work? Something like a callback to paypal.com to get the verification? (Analogous to downloading an SSL cert from a website without using a trusted side channel like a handwritten note?)