The sad part is that the companies will use this security by obscurity argument against open sourcing.
Obscurity is good practice as one layer of a layered defence system.
See "Defence in Depth" https://en.wikipedia.org/wiki/Defense_in_depth_(computing)
"Defense in depth is originally a military strategy that seeks to delay rather than prevent the advance of an attacker by yielding space to buy time".
We have to acknowledge that no system is perfect, there will always be holes, therefore a good approach is to layer up the imperfect systems which delays the attacker.
Obscurity is one of those layers, a system will always be more secure if you have to find it first.
its one part of a whole system, and in that, if it does delay or deter (even slightly) then it has worked.
The trust question is the problem with obscurity. Do you trust the people making it obscure?
In this particular case, where safety-critical standards are relatively well known (within the industry) and not themselves obscured, they deserve to be trusted.
Do we trust them or not?
The problem with VW was not a 'bug'. it was a malicious design.
After all, if you're a system maker, why would you hire hardasses who have rejected your products in the past? And if you're a certification house, why would you $$$ on many hours from experienced engineers when you could use fewer hours and junior employees giving you happier customers and higher profit margins at the same time?
You can hire "independent" people to tell you what you want in a lot of industries. You want an "independent salary survey" to tell you that $50,000 is the market rate for an experienced programmer, but that your CEO needs a $5 million raise? Or an "independent credit rating agency" to tell you your subprime mortgage backed security is triple-A rated? The free market will happily provide such "independent" reports at the right price.
But the government(s) also employs similar agencies to perform the enforcement of the certifications.
Its not a perfect system, but its a lot better than the developer-on-the-street realises.
It's like when you leave a key for someone under a door mat. You don't often consider that the door might be easily kicked in by an intruder.
Thats the problem right there.... not obscurity.
This applies to security and safety. There is no reason not to implement obscurity also.
One thing I can guarantee is that your implementation of one security-type will not be unbreakable.... and neither will mine.
Better to add obscurity than not.
For example, hiding the algorithm from whitehats may prevent/discourage them from hunting/reporting bugs.
Yea, this is a serious concern, I guess it depends on use cases. For sure "security by obscurity considered harmful" could be true, thats the thing people overgeneralize and fight over it when this should be weighted depending on the circumstances.
I think the big problem with obscurity is that its impact is asymmetric in the wrong direction: it inconveniences white hats a lot more than black hats.
Even if mathematically unbreakable, the implementation won't be.
This is the whole premise of defence-in-depth... delay rather than prevent.
An acceptably low break in rare using mathematically valid encryption.... Yes, fine... Given a perfect implementation.
You haven't got one of those.
I don't think it's too much to ask before adopting a given security policy that it provide some evidence that it increases security. Or should I also be gathering a collection of rocks that keep hackers away?
1# security by obscurity gives a false sense of security. Under no circumstance should obscurity be used as a deciding factor behind a management decision.
2# security by obscurity cost money and time, and should only be used when all real form of security measures has been implemented. Even the military are currently not always implementing multi-token authentication, ipsec and selinux. Instead of trusting that the medical deceive is safe behind two layers, a static password and a secret port, add a certificate and implement challenge and response.
3# the priority to implement security by obscurity should be far lower than all the real security technologies. When reading security reports by pen testers, its important to understand the difference between a verified code injection vulnerability and a system information disclosure. Fixing a remotely code injection bug is much more important than hiding the fact that a system is running a up-to-date stable version of Debian, yet many security guides and reports for pen-testing tools rarely priorities.
4# security by obscurity often has real cost in support, brittleness of the system, and debugging. There is still in 2016 firewalls that will permanent block any ip address that has sent a icmp package to them. The amount of work employees are spending to unblock customers that accidentally end up in the block list could be spent on making sure that the system is just that more perfect against the serious attackers who can afford to spend $50 to access a botnet for a few hours.
Its common sense that I can't pick a lock if I cant find the lock.
This says nothing about the quality of the lock or what is behind the lock.
Spending time on security by obscurity should be a job for the small minority of people who already done everything else, and then only if there is a cost-benefit analyze that show cost of the obscurity to be less than the calculated gains.
These types of products are entirely designed up front and analysed before any code is written so the implementation order is irrelevant.
Obscurity don't scale. Things that are commonly used should not use obscurity.
Somebody who mass produces computing equipment or software that many use can't use obscurity because it's economically efficient for attackers to look past obscurity. It's also unproductive to advice others to use some obscuring methods, because as soon as something becomes even slightly common, it can be detected and security of obscurity vanishes.
Obscurity must be obscure. Great minds think alike and it's very easy to build obscurity that is similar to what everyone else thinks is nice trick.
Genuine obscurity can provides additional security layer (in probabilistic expected value sense) against automatic or routine attacks. If obscurity requires even small time to figure it out, it's likely that attacker moves to next target. But it's hard to know how well the obscurity is working.
Practically speaking, obscurity is a "platform" that lets you bypass everything, whereas knowing a password is more limited since it grants access to a single user. But practically speaking, obscurity and root passwords are similar..
I wonder if there are formal definitions here that makes the separation clear.
Locks are rated in how many seconds/minutes they can withstand from a dedicated attacker. Perhaps that would be a way to determine a similar safety rating for passwords/crypto based systems.
In passwords: how many passwords can you try per second before the server refuses? Then Password space/# per second = total seconds for guaranteed entry.
Crypto: how many keys do you have to calculate before you succeed in finding the correct key? Keys/second * how many machines / keyspace.
But in the end, I don't believe we really have a formalized difference between types of obscurities, aside the "go to /root and get root" obvious badness. It would be a rather nice way to provide security in "seconds to millenia depending on techniques used".
Most individuals defending algorithmic security through obscurity believe that hiding the algorithm improves security. That may be true in an extremely technical sense (the attacker must recover the algorithm first), but it is very misleading and unprofessional commentary. Algorithmic security through obscurity is at best calculated in difficulty-to-reverse-engineer (or difficulty-to-steal), which doesn't provide per-use(r) specificity (per-user password) nor scale in complexity (a 256-bit key is generally 2^128 times stronger than a 128-bit key, but doubling the algorithm length increases reversing time by slightly less than a factor of 2).
Algorithmic security through obscurity provides negligible security, but what's the harm? Why should we care? Attempting to hide the algorithm provides a false sense of security, limits review to "approved" parties, and induces legal/social efforts to "protect" the secret. The limited review is particularly noteworthy since it promotes bugs in both the algorithm and the implementation. The end result is a facade of security, some very unhappy whitehats, some very happy blackhats, and more users betrayed through poor security practices.
[1] http://csrc.nist.gov/publications/nistpubs/800-57/sp800-57_p... [2] http://tjscott.net/crypto/64bitcrack.htm#INTELG
The major difference here is this: with security through obscurity, someone can reverse engineer one product and then they've broken all products. This is why someone upstream said "security through obscurity doesn't scale". Security through obscurity is often okay if you're protecting one thing, but if you're using it to protect a system (like a pacemaker) that is going to be used by a lot of people, the more people who use it, the more valuable a reverse engineering hack becomes. Security through obscurity can't be individualized to provide security to each individual--if one system is broken all systems are broken.
Compare this with key-based security--if each instance of the system has an individual, randomized key with a large enough keyspace, breaking a key will only get you into a single instance of the system. It scales because the reward for breaking the security doesn't grow as the number of system instances grows.
Note that the problem with security through obscurity is basically the same problem with master keys, i.e. those used for backdoors or DRM. If someone can obtain the master key for the system, they can break all the instances of the system.
It is much harder to formalise how hard it is for an attacker to find out what algorithm you use, so it is risky relying too much on him not being able to do so.
It's qualitative versus quantitative. Security is a quality, which means it can become absolute: the complete absence of security holes. Obscurity, on the other hand, is quantitative, because you can always add more obscurity. There is no "absolute" obscurity.
"Buying time" doesn't make sense in this context. It's pacemaker software. Who's buying time by making proprietary pacemaker software and for what reason?
Buying time is only useful if you can see when an attacker begins trying to subvert your system. If he can sit at home working on it for a year, "buying time" to improve security makes no sense, as you can't spend the time to improve security,p when you don't know you're about to be attacked.
No layer of security is ever perfectly implemented, mathematically perfect tho the algorithms may be.... this is the key point that defence-in-depth acknowledges... and hence is the key point that obscurity addresses.
Buying time certainly does gain you a lot in this context. If someone was attempting to bypass security to get into a pacemaker in side me.... I would damn-sure prefer the apparent "lock" to be hidden rather than in plain sight! (given everything else is equal).
I would prefer the lock be visible to me over either situation. Otherwise, how would I know how easy is it to bypass?