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[return to "A case against security nihilism"]
1. static+Di[view] [source] 2021-07-20 20:50:05
>>feross+(OP)
Just the other day I suggested using a yubikey, and someone linked me to the Titan sidechannel where researchers demonstrated that, with persistent access, and a dozen hours of work, they could break the guarantees of a Titan chip[0]. They said "an attacker will just steal it". The researchers, on the other hand, stressed how very fundamentally difficult this was to pull off due to very limited attack surface.

This is the sort of absolutism that is so pointless.

At the same time, what's equally frustrating to me is defense without a threat model. "We'll randomize this value so it's harder to guess" without asking who's guessing, how often they can guess, how you'll randomize it, how you'll keep it a secret, etc. "Defense in depth" has become a nonsense term.

The use of memory unsafe languages for parsing untrusted input is just wild. I'm glad that I'm working in a time where I can build all of my parsers and attack surface in Rust and just think way, way less about this.

I'll also link this talk[1], for the millionth time. It's Rob Joyce, chief of the NSA's TAO, talking about how to make NSA's TAO's job harder.

[0] https://arstechnica.com/information-technology/2021/01/hacke...

[1] https://www.youtube.com/watch?v=bDJb8WOJYdA

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2. blowsk+uk[view] [source] 2021-07-20 20:59:32
>>static+Di
I was with you until the parsing with memory unsafe languages. Isn’t that exactly the kind of “random security not based on a threat model” type comment you so rightly criticised in the first half of your comment?
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3. kmeist+iq[view] [source] 2021-07-20 21:27:30
>>blowsk+uk
There are very few threat models that a memory unsafe parser does not break.

Even the "unskilled attacker trying other people's vulns" threat basically depends on the existence of memory-safety related vulnerabilities.

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4. blowsk+2w[view] [source] 2021-07-20 22:05:02
>>kmeist+iq
Then we’re right back in the checklist mentality of “500 things secure apps never do”. I could talk to somebody else and they’d tell me the real threat to worry about is phishing or poor CI/CD or insecure passwords or whatever.
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5. static+nx[view] [source] 2021-07-20 22:16:11
>>blowsk+2w
There is no "real threat". Definitely phishing is one of the top threats to an organization, left unmitigated. Thankfully, we now have unphishable 2FA, so you can mitigate it. When you choose to prioritize a threat is going to be a call you have to make as the owner of your company's security posture - maybe phishing is above memory safety for you, I can't say.

What I can say is that parsing untrusted data in C is very risky. I can't say it is more risky than phishing for you, or more risky than anything else. I lack the context to do so.

That said, a really easy solution might be to just not do that. Just like... don't parse untrusted input in C. If that's hard for you, so be it, again I lack context. But that's my general advice - don't do it.

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6. lansti+NA[view] [source] 2021-07-20 22:46:09
>>static+nx
In-arguable these days.
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