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Here is a recent attack showing the lack of resilience in the CA ecosystem: https://freedom-to-tinker.com/2022/03/09/attackers-exploit-fundamental-flaw-in-the-w

by phicoh 2y ago

Here is a recent attack showing the lack of resilience in the CA ecosystem: https://freedom-to-tinker.com/2022/03/09/attackers-exploit-fundamental-flaw-in-the-webs-security-to-steal-2-million-in-cryptocurrency/ https://freedom-to-tinker.com/2022/03/09/attackers-exploit-f... With password resets your own mail server is not involved. STARTTLS or not. In the absence of DANE, mail servers will not require or validate certificates. So the reset link will get to the attacker in the vast majority of cases.

PreInternet01 2y ago
Yeah, password reset emails are sure a huge vulnerability. Nothing to do with DANE, though, since that won't solve that issue either (not going to spell out all the reasons for that, but suffice to say that once a zone's registrar account is compromised, as with all examples so far here, the 'turn off DNSSEC' option is even deadlier than all other extremely practical attacks otherwise possible against the protocol...)
tptacek 2y ago
These are attackers exploiting BGP. They can bypass DNSSEC, too. DNS is control of names; BGP is control of the underlying IPs.
- phicoh 2y ago
  Maybe you can be a bit more specific and explain how exploiting BGP can change the CAA record in a DNSSEC secured zone? ACME validation with dns-01 relies only on DNS. Routing does not matter other than to create DoS.
  - PreInternet01 2y ago
    It's simply one more step in an attack chain. Again, all of the examples mentioned upthread involve compromising the zone's registrar accounts (through old-fashioned 'spear-phishing', which works regardless of DNSSEC, DANE, 2FA, or whatever -- otherwise, we wouldn't be reading about it!). The argument "well, they were able to compromise BGP, but DANE surely would have stopped them" is not only unsupported, but not particularly likely either.
    - phicoh 2y ago
      Where do you find an attack on a registrar account in the following attack: https://freedom-to-tinker.com/2022/03/09/attackers-exploit-fundamental-flaw-in-the-webs-security-to-steal-2-million-in-cryptocurrency/ https://freedom-to-tinker.com/2022/03/09/attackers-exploit-f... I can't find it.
      - PreInternet01 2y ago
        I can't find it either, but that's just because I don't read Korean and can't deep-dive into the actual attack details, hidden behind the summary you posted. But let me pose a counterfactual: I am the owner of example.nl, and I publish the memoirs of one YA, which the .nl government desperately wants to suppress, for, eh, reasons. The .nl zone requires DNSSEC by default, but I cleverly host my zone on CloudFlare and disable DNSSEC. I also use LetsEncrypt to secure my site, which is only available via HTTPS. In response, the .nl government instructs all ISPs in the entire EU to route all CloudFlare traffic to its middlebox, and it obtains an SSL certificate in example.nl's name from Diginotar, a notably reputable SSL vendor. It uses all that power to host an alternative version of YA's memoirs. Which percentage of Internet users will actually see that alternative version? And how many millions of Euros will I be able to collect from the lawsuits afterwards? Bonus question: how much will it cost to replace the melted-down middlebox?
        effie 2y ago
        Wait, is this for real, or an hypothetical example? Where can I read the memoirs?

by phicoh 2y ago

PreInternet01 2y ago

Yeah, password reset emails are sure a huge vulnerability. Nothing to do with DANE, though, since that won't solve that issue either (not going to spell out all the reasons for that, but suffice to say that once a zone's registrar account is compromised, as with all examples so far here, the 'turn off DNSSEC' option is even deadlier than all other extremely practical attacks otherwise possible against the protocol...)

tptacek 2y ago

These are attackers exploiting BGP. They can bypass DNSSEC, too. DNS is control of names; BGP is control of the underlying IPs.

phicoh 2y ago
Maybe you can be a bit more specific and explain how exploiting BGP can change the CAA record in a DNSSEC secured zone? ACME validation with dns-01 relies only on DNS. Routing does not matter other than to create DoS.
- PreInternet01 2y ago
  It's simply one more step in an attack chain. Again, all of the examples mentioned upthread involve compromising the zone's registrar accounts (through old-fashioned 'spear-phishing', which works regardless of DNSSEC, DANE, 2FA, or whatever -- otherwise, we wouldn't be reading about it!). The argument "well, they were able to compromise BGP, but DANE surely would have stopped them" is not only unsupported, but not particularly likely either.
  - phicoh 2y ago
    Where do you find an attack on a registrar account in the following attack: https://freedom-to-tinker.com/2022/03/09/attackers-exploit-fundamental-flaw-in-the-webs-security-to-steal-2-million-in-cryptocurrency/ https://freedom-to-tinker.com/2022/03/09/attackers-exploit-f... I can't find it.
    - PreInternet01 2y ago
      I can't find it either, but that's just because I don't read Korean and can't deep-dive into the actual attack details, hidden behind the summary you posted. But let me pose a counterfactual: I am the owner of example.nl, and I publish the memoirs of one YA, which the .nl government desperately wants to suppress, for, eh, reasons. The .nl zone requires DNSSEC by default, but I cleverly host my zone on CloudFlare and disable DNSSEC. I also use LetsEncrypt to secure my site, which is only available via HTTPS. In response, the .nl government instructs all ISPs in the entire EU to route all CloudFlare traffic to its middlebox, and it obtains an SSL certificate in example.nl's name from Diginotar, a notably reputable SSL vendor. It uses all that power to host an alternative version of YA's memoirs. Which percentage of Internet users will actually see that alternative version? And how many millions of Euros will I be able to collect from the lawsuits afterwards? Bonus question: how much will it cost to replace the melted-down middlebox?
      - effie 2y ago
        Wait, is this for real, or an hypothetical example? Where can I read the memoirs?