The issuing was detected almost immediacy thanks to CT, and as we move to shorter certificate lifetimes the impact is continually reducing.
The CAA record in dns is a weak link though.
When a company has 3 billion customers, there's no practical cert lifetime that really reduces exposure. Five minutes would sniff enough traffic to do significant damage; one day would impact a big chunk of their users and five days would be nearly 100%
Which means that the risk to you or I or the general public is low.
But FWIW: it also tends to argue that this is the aftermath of a coordinated, targeted attack against a single high value target (or at most a small set of targets they could hit within the window). The attacker knew they had a gun with only one bullet, and we're just hearing the muzzle report.
HPKP was deprecated because it was too dangerous to be deployed in production.
If your CA certs are bad on your mobile application, you can push an out-of-band update via the device's app store.
If your CA certs are bad on a website you access via your browser, the means of updating them is... the browser. You can't get new certs without using a TLS connection you didn't want to trust anyway.
1) Top level CC DNS entries were hacked
2) CAA entries were removed (I assume google had them -- they do now CAA 0 issue "pki.goog"
3) These were then used to verify issuing certificates against major CAs (letsencrypt etc) - for example by creating a new CNAME record for DNS verification
Looking at google.as specifically shows Let's Encrypt issuing a certificate on 2026-09-27
https://ctlogs.dev/search?q=google.as
Google normally issues certificates with "Google Trust Services", presumably their in house CA which all browsers trust, but the only way to limit issuing to Google is with the CAA record.
If you hijack DNS, you hijack certificate issuing. As several CAs exist with no business relationship to identify the real person asking for the certificate, you can do this anonymously. (If CAs required verification then you'd just have to chain this with the stolen credentials of someone who uses that CA so wouldn't be a major obstacle)
From what I can tell (and the article conflates this with the diginoir so implies it), this was NOT a compromise of a Certificate Authority
AS: American Samoa
GH: Greenland
SL: Sierra Leone
I misread.
Thanks for the correction.
"These incidents did not involve a compromise of Google’s systems; rather, attackers compromised the third-party ccTLDs, putting any domain ending in .gh, .sl, or .as at risk. During these hijacks, attackers modified authoritative DNS records and obtained unauthorized HTTPS certificates covering several Google domains, as well as domains belonging to other organizations."
So entire top level domain registries were compromised. Interesting times. Isn't there really any primary source on this?
But a compromise of Google's users.
I think we are potentially being told Google has domain names but no employees in those countries. This otherwise sounds quite implausible, and I don't know enough to say Google is lying.
Did it? If you get a link to google.gh, did you at any point assume that's the real Google?
Is it TLDs lacking support for this?
Did you know you're allowed to own an IP address block without making it publicly routable? They will have to periodically call you to make sure you're still using it, but it's otherwise allowed.
Edit: Someone more curious than I am might be able to answer this by seeing when the CRLSet was published. https://github.com/agl/crlset-tools
Hell:
$ curl www.google.es
<HTML><HEAD><meta http-equiv="content-type" content="text/html;charset=utf-8">
<TITLE>301 Moved</TITLE></HEAD><BODY>
<H1>301 Moved</H1>
The document has moved
<A HREF="http://www.google.com/">here</A>.
</BODY></HTML>General solutions are tricker, and it’s good that Google limits its “special” case. When bbc.com or al jazzera or cnbc or whatever is hacked that’s a problem that is only solved by generic solutions.
What I'd like to see is the ability to use and utilise multiple TLS certificates and host keys on the same session so that all the keys could be rotated/phased in-band with cross-signing providing the authority.
Seeing any mere change in the signers faster than (say) 30 days should allow the browser/client-stack to generate a warning that "google.com may be actively under attack please call this number on the old certificate, codeword banana-alpha-lima-lima-sigma". No need to cross-publish the keys, just cross-sign and don't forget what you've seen previously.
The browser would be able to take policy of simply never trust a certificate whose signer has changed (since phasing is possible), and it wouldn't then need to consult more public oracles (DNS, certificate transparency, etc, that leak privacy).
I'd also like to get that webauthn hooked back into TLS client certificates: If we had 1997 again instead of passkeys that also would've stopped this.
This assumes that the signer's keys can't be compromised, and re-introduces the issues of key pinning that the WebPKI community has been pushing very hard to eliminate from its dependents. I don't think it's a workable solution.
Therefore either
1) Letsencrypt ignore CAA records (unlikely)
2) The DNS hijackers removed the CAA record 12+ hours before doing their attack and google did not notice (I'd hope unlikely)
3) Letsencrypt querys did not return a cached CAA record because their resolvers had not been asked for it, so removing the CAA record a few minutes before hand worked.
> .com may be actively under attack please call this number on the old certificate, codeword banana-alpha-lima-lima-sigma
Do you seriously think this is an appropriate message to give to Aunt Irene?
Or, if the signer's keys are compromised, how do you switch to a non-compromised signer without alarms triggering?
The problem is almost exactly the same as one with a delegated CA -- if the CA keys are compromised, you have to re-issue all certs. When the client pins the CA key then the chain of trust is permanently broken.
You mean, hypothetically if Letsencrypt suddenly loses the ability to sign new requests from me?
Well, then I have around 30 days to detect that and choose a new signer.
> Or, if the signer's keys are compromised, how do you switch to a non-compromised signer without alarms triggering?
Again, to be clear, you're talking about Letsencrypt's own signing keys in this case, being compromised and them being denied access to them. That seems incredibly unlikely to have both failures at the same time, but again: I have 30 days to find a new signer.
> The problem is almost exactly the same as one with a delegated CA -- if the CA keys are compromised
No! In fact, if Letsencrypt sublicenses signing to a third-party that certificate would be considered separate and so the switcheroo would be detected!
> When the client pins the CA key then the chain of trust is permanently broken
That's why it is important to extend TLS to allow multiple keypairs and certificates to be used to mutually authenticate the session key, so that any of the previous pinned keys can be used to update the pin. I did not say I wanted this for no reason!