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Comment by ggeorgovassilis | Hacker News Reader

This story has been widely under-reported and the impact is potentially huge. My beef with MS is this: the keys were leaked in 2021 and were still signing authentication tokens in 2023, but there's not a single Azure service that allows me to enter credentials with a 2 years duration. It's a classic case of "do as I say, not as I do".

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Imagine what the CA/Browser Forum would do if they discovered that a PKIX CA had lost control of its signing keys, didn't revoke them and in fact carried on using them for 2 years without telling anyone...

Have you checked if you have a Microsoft CA installed to your system?

I simply assume Microsoft have already compromised my systems already. :)

More seriously, on my Debian stable system:

    $ dpkg -l ca-certificates
    Desired=Unknown/Install/Remove/Purge/Hold
    | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
    |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
    ||/ Name            Version      Architecture Description
    +++-===============-============-============-=================================
    ii  ca-certificates 20230311     all          Common CA certificates
    
    $ trust list | grep Microsoft
        label: Microsoft ECC Root Certificate Authority 2017
        label: Microsoft RSA Root Certificate Authority 2017

On RHEL 9:

    $ rpm -q ca-certificates
    ca-certificates-2023.2.60_v7.0.306-90.1.el9_2.noarch
    
    $ trust list | grep Microsoft
        label: Microsoft ECC Product Root Certificate Authority 2018
        label: Microsoft ECC Root Certificate Authority 2017
        label: Microsoft ECC TS Root Certificate Authority 2018
        label: Microsoft Identity Verification Root Certificate Authority 2020
        label: Microsoft RSA Root Certificate Authority 2017
        label: Microsoft Root Authority
        label: Microsoft Root Certificate Authority
        label: Microsoft Root Certificate Authority 2010
        label: Microsoft Root Certificate Authority 2011
        label: Symantec Enterprise Mobile Root for Microsoft

Interesting that RHEL has many more certificates, when both packages take whatever's bundled into NSS.

According to 'rpm -q --changelog ca-certificates' RHEL take their certs from "CKBI 2.60_v7.0.306 from NSS 3.91" and according to /usr/share/doc/ca-certificates/changelog.Debian.gz, Debian take theirs from "Mozilla certificate authority bundle" 2.60.

And so, to back to your question:

> Imagine what the CA/Browser Forum would do if they discovered that a PKIX CA had lost control of its signing keys, didn't revoke them and in fact carried on using them for 2 years without telling anyone...

Are these certificates affected? Or perhaps the CA/Browser Forum aren't aware of the scope.

I sure hope not. But I suppose only Microsoft are able to confirm whether their PKIX CA private keys are or are not affected by their various security incidents, including the Azure token leak mentioned by ggeorgovassilis.

Are you aware of what applications and services are verified by these keys? I am thinking it might be worth removing these specific root certificates if they are used only for a select number of purposes, considering that the vast majority of 'normal' websites use other CAs like DigiCert or Let's Encrypt.

Among other things, Azure services use certificates issued by those issuers.

This. They don’t even use a HSM if I understood correctly and using one is not part of the mitigation plan. Not OK.

HSM’s are super inconvenient obviously, and as Mr. Robot showed not perfect. So why bother? /s

Apparently they might also be backdoored by the NSA: https://news.ycombinator.com/item?id=37571014

Still probably better than having the private key part of a random core dump from a random developer. :s

That’s just embarrassing.

No doubt. My expectations to MS engineering are really low so I'm unfortunately not shocked.

Frankly is this important? If the NSA is a threat to you do you have any business trusting MS?

No one has any business trusting Microsoft, apparently?

I’m under no delusions that an intelligence agency with ‘home team advantage’ wouldn’t already have the keys to the kingdom. If they are in the apparent habit of leaving the keys sitting around in random Cafes, the odds that other non-home team intelligence agencies have a copy increases dramatically too. Or even random miscreants.

As to if that matters? Eh.

They sure sell HSM on Azure.

The worst part of the story to me is —- those were not even the right keys, those were something issued to a client and scoped, but scoping check was broken. It’s unbelievably bad all around

Close, but not quite. The keys were for consumer Microsoft accounts, but accepted for organization accounts as well.

You can still create "app registration secrets" that last for up to two years. Until recently, you could create essentially unlimited-duration secrets.

It's only a limitation in the UI. Using powershell you can still create client secrets that are valid for hundreds of years.

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