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Security through obscurity is not bad

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131–140 of 228 posts

Re: Security through obscurity is not bad

#131

Obscurity is not security. But it can add a bit of delay to someone breaking actual security, so maybe they'll hit the next target first as that is a touch easier. Though with the increasing automation of hole detection and exploitation, even that might stop being the case if it hasn't already. The biggest problem with obscurity measures IMO is psychological: people tend to assume that the measures⁰ are far more effe…

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Re: Security through obscurity is not bad

#132
post #126
post #111

Earlier quoted context omitted.

> All modes of cyber security depend on some obscurity (e.g. password) That's not what the expression means. "Security through obscurity" has a very specific meaning — that your system's security depends on your adversary not understanding how it works. E.g. understanding RSA is a few wikipedia articles away, and that doesn't compromise its security, so RSA isn't security through obscurity.

Lucketone likely knows this and was pointing out that "obscurity" is a misleading word to use when talking about systems which all rely on obscurity, in the plain English sense of the word.

We're in a technical forum, discussing a term of art that refers to a very specific bad practice.

Lucketone's argument is essentially saying that the bad practice itself isn't actually a bad practice by equivocating the term of art and the plain language definition.

Re: Security through obscurity is not bad

#134

I get what this post is saying, but I'm going to push back that "security through obscurity" isn't just something that people parrot without understanding. Obscurity provides, effectively, no security. There may be other benefits to the obscurity, but considering the obscurity a layer of your security is bad . I hope we all agree that moving telnet to another port provides no security (it's easily sniffable, easily f…

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Re: Security through obscurity is not bad

#135

Earlier quoted context omitted.

I don't think that really works because obscurity isn't harder to see or find. I don't know the analogy, it's like standing out in the open and being like "yeah but who would think to look here lol".

I think you're misinterpreting "obscurity" for "lack of obscurity". If you have a vulnerability in an API interface that is completely undocumented that is a vulnerability that is obscured. It's hiding in the woods, not standing in a field. To keep with the analogy: no one is going to stand in a field when people are shooting at you. So then why do a small subset of vocal people online suggest that you just put your…

You know when people are shooting at you. You don't know when or if people are exploring undocumented/obscure features of your system and what they have learned about it that you were trying to hide.

Therefore, the safest assumption to make is that an adversary already has figured out all of your obscurity, because they always can do this given sufficient time and interest, at which point the only thing between them and you is your security.

That is why we design systems without obscurity and only care about security.

Re: Security through obscurity is not bad

#136
post #111

Earlier quoted context omitted.

> All modes of cyber security depend on some obscurity (e.g. password) That's not what the expression means. "Security through obscurity" has a very specific meaning — that your system's security depends on your adversary not understanding how it works. E.g. understanding RSA is a few wikipedia articles away, and that doesn't compromise its security, so RSA isn't security through obscurity.

No, "Security through obscurity" is a valid and useful layer. A lot of weight hangs on your word “depends” though, in which case if it is the only layer then you will eventually have, uh, problems. I’ve used it for a long long time. Like in 1999 I’d have a knock on certain ports in a certain order to unlock the ssh port. And lots of weird stuff to stop forum spam. Which could work for weeks or months or even a year.

Port knocking isn't security through obscurity. Given the knowledge that you have a port knocking system in place doesn't tell me what specific sequence of knocks will open up the service I want to target. Even just a two knock sequence gives you a key with 32 bits of entropy, which makes it trivial to block attempts at bruteforcing the key.

Re: Security through obscurity is not bad

#137

Earlier quoted context omitted.

I think you're misinterpreting "obscurity" for "lack of obscurity". If you have a vulnerability in an API interface that is completely undocumented that is a vulnerability that is obscured. It's hiding in the woods, not standing in a field. To keep with the analogy: no one is going to stand in a field when people are shooting at you. So then why do a small subset of vocal people online suggest that you just put your…

You know when people are shooting at you. You don't know when or if people are exploring undocumented/obscure features of your system and what they have learned about it that you were trying to hide. Therefore, the safest assumption to make is that an adversary already has figured out all of your obscurity, because they always can do this given sufficient time and interest, at which point the only thing between them…

I agree that it's a good principle but it's taken too far when justifying needlessly growing risk surface area. Like the principle is useful to justify security hardening. It is not useful when used to increase the odds of being attacked.

Re: Security through obscurity is not bad

#138

> Security ONLY through obscurity is bad (Kerckhoffs's Principle). This is the crux of the article. (1) Kerckhoffs's Principle doesn’t say that. It says to design the system AS IF the adversary has all of the info about it except the secrets (encryption key, certificates, etc). (2) this rule is okay if you are a solo maintainer of a WordPress installation. It’s a problem if you work at a large company and part of the…

Kerkhoff's principle is not about security in general, it is about the design of cryptography. Assume your opponent knows everything about how your crypto system works. Your security then lies in the keys and not knowledge of the method. More broadly, anything that raises the cost of an attack helps security. Whether it is worth investing your defensive effort in that vs on more actual security is a different matter.

I agree, that anything that raises the cost of an attack may be worth doing. Most “obscurity” related practices do not meaningfully raise the cost of an attack beyond a certain threshold. Physical locks are not a great analogy.

Re: Security through obscurity is not bad

#139

Earlier quoted context omitted.

This isn't about what's a good idea or bad idea. Perhaps it's best to simply leave analogies behind, otherwise we'll just focus on the wrong thing. Security through obscurity merely means that your system is atypical. It's not hidden, it's not secret, it's not hard to find, it's not hard to examine, it's not less visible, etc - there is nothing inherently different about the systems at all other than that one is more…

I'm having a hard time understanding what you mean here. If something is obscured, by definition it is less visible. Being 'less typical' is a form of security because most attacks rely on some form of pattern recognition, and obscurity literally dissolves patterns into noise.

You're overly focusing on the term and not the meaning. The term comes about from people choosing tools like "foxit" or "Opera" and saying that those products are safer than their cohorts Adobe/ Firefox because they are attacked less often.

This notion was termed "security through obscurity" ie: "you use the less popular option, therefor that option is safer". It has nothing to do with "obscuring" in the sense of "hiding", that's a linguistic quirk of a colloquial term. If you were actually taking action to reduce the ability to understand a system in a way that you could meaningfully defend, it would no longer be "security through obscurity".

The argument has persisted because there are two different questions that sound the same (X is less typical than Y):

1. Is "X" safer than "Y"?

2. Is a user of "X" safer than a user of "Y"?

When looking at (1) in isolation, you can say things like "X lacks security features, therefor Y is safer" and "X is less often used, therefor X is safer", etc. This is a question about the posture of the project itself, in isolation.

(2) is about the context for users. The reality is that X, which perhaps is fundamentally less well built software, may actually have users who are attacked far less frequently.

Both are likely to favor "rarity is a poor indicator of safety" as we generally reject mitigation approaches that rely on attackers to behave specific ways, but what's important is that these are completely different questions and neither has to do with being obscured but rather rare.

None of this is about what is "obscured" or not. If something is obscured or obfuscated, that is a technique that can be evaluated separately by its own merits (ie: how hard is deobfuscation, how easy is it to adapt to deobfuscation, etc). All of this is about whether you're evaluating (1) or (2) - and in the case of (1), which is what the criticism always has focused on, the answer is that "rarity" is not a mitigation.

Re: Security through obscurity is not bad

#140

Earlier quoted context omitted.

This isn't about what's a good idea or bad idea. Perhaps it's best to simply leave analogies behind, otherwise we'll just focus on the wrong thing. Security through obscurity merely means that your system is atypical. It's not hidden, it's not secret, it's not hard to find, it's not hard to examine, it's not less visible, etc - there is nothing inherently different about the systems at all other than that one is more…

What you're describing is a thing that is not obscured. Don't refer to things as obscured if they are not obscured. When others talk about about things that are obscured they are talking about things that are obscured, not things that are not obscured.

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