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Twitter has an internal root CA problem

izzodlaw.com

11–20 of 79 posts

Re: Twitter has an internal root CA problem

#11
Taking it with a pinch of salt, but this stuff does happen.

I've received calls from past employers, usually when they migrate a site I worked on to a new CMS or platform. There is some critical service (AWS, CDN credentials, domain related) etc. that no one knows who has access... Happily those appear to get resolved... but this... yikes (if true)

Re: Twitter has an internal root CA problem

#12
post #5

If this is true - who knows - then it reflects rather badly on the people who were fired - as they didn't implement safeguard for a 'run over by a bus' scenario when they were in charge.

Maybe building it right cost 5x, and you have a budget for 1x. Sometime money is not unlimited even at FAANG

To add on, people forget that Twitter was never really FAANG. It not only wasn't profitable but had no monetization plan for years. I'm sure it paid off for all the investors who got Elon's money but even as a Facebook competitor they don't have Facebook money.

Re: Twitter has an internal root CA problem

#13

If this is true - who knows - then it reflects rather badly on the people who were fired - as they didn't implement safeguard for a 'run over by a bus' scenario when they were in charge.

It reflects rather badly on you that you're talking mad shit without knowing their circumstances. What's the bus factor on your systems? Can they handle literally every person being fired overnight?

Re: Twitter has an internal root CA problem

#15
Oh, I know that problem, we did change Puppet root CA due to mishap of one of the admins during updating to sha256 certs. But IIRC (it was long time ago) Puppet CA cert by default are issued for like 10-20 years, would be a bit weird if true. Also, old versions didn't had trust chain "just" root CA so puppet master would have to have key for that on disk anyway, proper "root CA + leaf CA for puppetmasters" have been a thing for just few years in Puppet.

It would only be really problematic if they also lost SSH access to those machines using Puppet. If you have root access the fix is not exactly hard.

But then they fired people that did had access so that might also be a problem

We made sure all of our machines can be accesses both by Puppet and by SSH kinda for that reason; we had both accidents of someone fucking up Puppet, and someone fucking up SSH config rendering machines un-loggable (the lessons were learned and etched in stone).

So really, depending on who has access to what, it can be anything from "just pipe list of hosts to few ssh commands fixing it" to "get access manually to the server and change stuff, or redeploy machine from scratch". Again, assuming muski boy didn't fire wrong people

Re: Twitter has an internal root CA problem

#16

I'll take the rumor with a grain of salt, but can anyone unpack what the recovery plan would be for something like this? It would obviously be a big problem, but where would you even start?

Assuming they’ve still got access to the servers themselves via SSH, you’d start by issuing a new root CA cert for the Puppetmaster and putting that in place, then you’ve got to issue a new cert for every client and distributing those. It’s not impossible, but it’s also going to be a pain in the backside to do.

Been there before, we did exactly this; except over OOB+reboot-into-single-user (because SELinux). Took us a few days (~5k servers) but managed to get out of it with no public-facing downtime. The other way would have just been to rekick the world one box at a time. A number of integration tests were added after that disaster :)

Re: Twitter has an internal root CA problem

#17

I'll take the rumor with a grain of salt, but can anyone unpack what the recovery plan would be for something like this? It would obviously be a big problem, but where would you even start?

Create new root CA, ssh to machine, remove old certs, re-add machine to Puppet, sign the new CSR on Puppet master, then it will download new root.

Very simple operation... if you have working SSH access with root. If they don't, well...

Re: Twitter has an internal root CA problem

#18
post #11

Taking it with a pinch of salt, but this stuff does happen. I've received calls from past employers, usually when they migrate a site I worked on to a new CMS or platform. There is some critical service (AWS, CDN credentials, domain related) etc. that no one knows who has access... Happily those appear to get resolved... but this... yikes (if true)

Funnily enough putting it in configuration management (like Puppet) can make it nice and automatic.

But, well, if you fuck up your CM...

Re: Twitter has an internal root CA problem

#19

If this is true - who knows - then it reflects rather badly on the people who were fired - as they didn't implement safeguard for a 'run over by a bus' scenario when they were in charge.

There's "run over by a bus" and "90% of the company got ran over by a bus" scenarios. The second one is rarely worth implementing.

Not to forget the "90% get fired my an egotistical maniac who expressed his distain by quite publicly calling them lazy useless pieces of shit" scenario. That scenario is also seldom considered.

Re: Twitter has an internal root CA problem

#20
post #5

If this is true - who knows - then it reflects rather badly on the people who were fired - as they didn't implement safeguard for a 'run over by a bus' scenario when they were in charge.

Maybe building it right cost 5x, and you have a budget for 1x. Sometime money is not unlimited even at FAANG

We have 7 racks and 3 people working in ops and built Puppet setup "right". It's not hard. And their setup was probably right too.

Just that nobody plans for "bus hit our entire ops team"

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