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Getting ready to issue IP address certificates

(community.letsencrypt.org)
314 points Bogdanp | 1 comments | 25 Jun 25 16:21 UTC | HN request time: 0.206s | source
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lq9AJ8yrfs ◴[25 Jun 25 17:56 UTC] No.44380076[source]▶
So all the addressing bodies (e.g., ISPs and cloud providers) are on board then right? They sometimes cycle through IP's with great velocity. Faster than 6 days at least.

Lots of sport here, unless perhaps they cool off IPs before reallocating, or perhaps query and revoke any certs before reusing the IP?

If the addressing bodies are not on board then it's a user responsibility to validate the host header and reject unwanted IP address based connections until any legacy certs are gone / or revoke any legacy certs. Or just wait to use your shiny new IP?

I wonder how many IP certs you could get for how much money with the different cloud providers.

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gruez ◴[25 Jun 25 20:05 UTC] No.44381336[source]▶
>So all the addressing bodies (e.g., ISPs and cloud providers) are on board then right? They sometimes cycle through IP's with great velocity. Faster than 6 days at least.

>Lots of sport here, unless perhaps they cool off IPs before reallocating, or perhaps query and revoke any certs before reusing the IP?

I don't see how this is any different than custom/vanity domains you can get from cloud providers. For instance on azure you can assign a DNS name to your VMs in the form of myapp.westus.cloudapp.azure.com, and CAs will happily issue certificates for it[1]. There's no cooloff for those domains either, so theoretically someone else can snatch the domain from you if your VM gets decommissioned.

[1] https://crt.sh/?identity=westus.cloudapp.azure.com&exclude=e...

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1. briHass ◴[26 Jun 25 02:15 UTC] No.44383648[source]▶
This is why Azure now uses a unique hash appended to the hostname by default (can be changed if desired.) You can't attack a dangling CNAME subdomain record if it points to a hashed-appended hostname, and Azure allows you to control the uniqueness either globally/tenant/region so you can have common names in that tenant/region if you wish.