Fascinating and sophisticated MiTM ('man in the middle') at Hetzner (DE) and Linode, targeting Russia's largest XMPP/Jabber (civilian) chat service. The authors of the article make a reasonably compelling case that "this is lawful interception Hetzner and Linode were forced to setup."
notes.valdikss.org.ru/jabber.r…
Excellent mitigation walkthrough here:
Sure gets me thinking.
modulux
in reply to Julian Oliver • • •Regarding the LB, someone was wondering whether the FBI could circumvent SSL connections, and we have an answer: German police can.
Unfortunately I can't find the post asking that question, otherwise I'd reply directly to it.
Julian Oliver
in reply to modulux • • •old sysops
in reply to Julian Oliver • • •If you have a legal power to compel a hosting compagny, you have it for a ca one.
But yes, dnssec and caa are in the critical path.
Julian Oliver
in reply to old sysops • • •modulux
in reply to Julian Oliver • • •Julian Oliver
in reply to modulux • • •modulux
in reply to Julian Oliver • • •I am not too familiar with CAA, but would this have helped in the first place? My understanding is CAA only says "such and such CA can authorise this domain." So if they were using LE before LE would be on the record and the attack would go through. Or am I missing something?
@oldsysops
Julian Oliver
in reply to modulux • • •In fact yes it can help in the case of LE, as you can define a record like so:
yourdomain.org CAA 128 issue "letsencrypt.org;accounturi=acme-v02.api.letsencrypt.org/a…<le-account-number>
However if the attacker has prior-knowledge your LE account number, then you only have DNSSEC.
modulux
in reply to Julian Oliver • • •Refurio Anachro
in reply to Julian Oliver • • •If your hoster is attacking you, they can just pick your cert's private keys off your box and use that. Neither CAA nor DNSSec will help.
@JulianOliver @modulux @oldsysops
modulux
in reply to Refurio Anachro • • •