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Showing posts with label security through obscurity. Show all posts
Showing posts with label security through obscurity. Show all posts
Monday, 4 January 2016
Saturday, 24 May 2014
eBay's Weak Security Architecture
Well eBay are in the news due to their breach of 145 million users' account details. There are a few worrying things about this breach, beyond the breach itself, that point to architectural issues in eBay's security.
The first issue is that a spokeswoman (according to Reuters) claimed "that it used 'sophisticated', proprietary hashing and salting technology to protect the passwords." This sounds very much like security through obscurity, which doesn't work. So, either they are using a proprietary implementation of a publicly known algorithm, or they have created their own. Both of these situations are doomed. As always, no one person can think of all the attacks on an algorithm, which is why we have public scrutiny. Even the best cryptographers in the world can't create new algorithms with acceptable levels of security every time. Do eBay have the best cryptographers in the world working for them? I don't believe so, but I could be wrong.
Also, if their argument is that hackers don't know the algorithm so can't attack it, then I'm fairly sure they're wrong there too. Even if the algorithm was secure enough to stand up to analysis of the hashes only, as hackers have eBay staff passwords perhaps they also have access to the code! If, on the other hand, they have their own implementation of a public algorithm I have to question why? Many examples are available of implementations that have gone wrong and introduced vulnerabilities, e.g. Heartbleed in OpenSSL. Do they think they know better?
The second issue is that they don't seem to encrypt Personally Identifiable Information (PII). This is obviously an issue if a breach should occur, but, admittedly, doesn't solve all problems as vulnerabilities in the web application could still expose the data. However, it is likely to have helped in this situation.
Finally, and most importantly, how did gaining access to eBay staff accounts give attackers access to the data? Database administrators shouldn't have access to read the data in the databases they manage. Why would they need it? Also, I would hope that there are VPNs between the corporate and production systems with 2-factor authentication. So how did they get in? Well, either eBay don't use this standard simple layer of protection, they leave their machines logged into the VPN for extended periods or they protect the VPN with the same password as their account.
Even if eBay do implement VPNs properly with 2-factor authentication, the production servers shouldn't have accounts on them that map to user accounts on the corporate network. Administrative accounts on production servers should have proper audited account control with single use passwords. Administrators should have to 'sign out' an account and be issued with a one-time password for it by the security group responsible for Identity and Access Management (IAM).
All this leads me to think that eBay have implemented a weak security architecture.
Also, if their argument is that hackers don't know the algorithm so can't attack it, then I'm fairly sure they're wrong there too. Even if the algorithm was secure enough to stand up to analysis of the hashes only, as hackers have eBay staff passwords perhaps they also have access to the code! If, on the other hand, they have their own implementation of a public algorithm I have to question why? Many examples are available of implementations that have gone wrong and introduced vulnerabilities, e.g. Heartbleed in OpenSSL. Do they think they know better?
The second issue is that they don't seem to encrypt Personally Identifiable Information (PII). This is obviously an issue if a breach should occur, but, admittedly, doesn't solve all problems as vulnerabilities in the web application could still expose the data. However, it is likely to have helped in this situation.
Finally, and most importantly, how did gaining access to eBay staff accounts give attackers access to the data? Database administrators shouldn't have access to read the data in the databases they manage. Why would they need it? Also, I would hope that there are VPNs between the corporate and production systems with 2-factor authentication. So how did they get in? Well, either eBay don't use this standard simple layer of protection, they leave their machines logged into the VPN for extended periods or they protect the VPN with the same password as their account.
Even if eBay do implement VPNs properly with 2-factor authentication, the production servers shouldn't have accounts on them that map to user accounts on the corporate network. Administrative accounts on production servers should have proper audited account control with single use passwords. Administrators should have to 'sign out' an account and be issued with a one-time password for it by the security group responsible for Identity and Access Management (IAM).
All this leads me to think that eBay have implemented a weak security architecture.
Saturday, 23 May 2009
Security Through Obscurity
I have been reminded recently, while looking at several products, that people still rely on the principle of 'security through obscurity.' This is the belief that your system/software/whatever is secure because potential hackers don't know it's there/how it works/etc. Although popular, this is a false belief. There are two aspects to this, the first is the SME who thinks that they're not a target for attack and nobody knows about their machines, so they're safe. This is forgivable if misguided and false. See my post about logging attack attempts on a home broadband connection with no advertised services or machines.
The second set of people is far less forgivable, and those are the security vendors. History has shown that open systems and standards have a far better chance of being secure in the long run. No one person can think of every possible attack on a system and therefore they can't secure a system alone. That is why we have RFCs to arrive at open standards that work. An example of a product that failed due to this is DiskLock. This was a few years ago now, but there are modern products that follow a similar philosophy. However, it's not my intention to pick on a particular vendor or product. DiskLock, though, was a program that encrypted files with the DES algorithm. No problems there, but they stored the key with the file, relying on people not knowing this or the scheme used to hide it. Unfortunately, with reverse engineering and chosen-key/plaintext attack techniques this is possible to work out. The problem is that the secrecy won't last long and when that has been bypassed the system should remain secure. If it does, then there was no need to keep it secret in the first place.
The only other time this phrase is used is when talking about the level of security given by implementing NAT. Here the addresses of the internal machines are obscured and an attacker doesn't know how many machines are there or what the internal topology is. Of course NAT will only allow outgoing connections or connections to specific ports due to port forwarding, so that does reduce the chances of attacking some machines. However, a web server will still have ports 80 and 443 open and, if it isn't properly patched, will suffer in exactly the same way as if it wasn't behind NAT.
I'm not saying that you should tell everyone exactly how you have implemented your security, but you can't rely on secrecy to last. The important thing is to thoroughly test your security, preferably with an outside independent agency. This is particularly important if you want others to rely on your system and must include an audit of your code for software and settings for your hardware. Are customers more likely to trust an independent testing agency or a vendor trying to sell a product or system?
The second set of people is far less forgivable, and those are the security vendors. History has shown that open systems and standards have a far better chance of being secure in the long run. No one person can think of every possible attack on a system and therefore they can't secure a system alone. That is why we have RFCs to arrive at open standards that work. An example of a product that failed due to this is DiskLock. This was a few years ago now, but there are modern products that follow a similar philosophy. However, it's not my intention to pick on a particular vendor or product. DiskLock, though, was a program that encrypted files with the DES algorithm. No problems there, but they stored the key with the file, relying on people not knowing this or the scheme used to hide it. Unfortunately, with reverse engineering and chosen-key/plaintext attack techniques this is possible to work out. The problem is that the secrecy won't last long and when that has been bypassed the system should remain secure. If it does, then there was no need to keep it secret in the first place.
The only other time this phrase is used is when talking about the level of security given by implementing NAT. Here the addresses of the internal machines are obscured and an attacker doesn't know how many machines are there or what the internal topology is. Of course NAT will only allow outgoing connections or connections to specific ports due to port forwarding, so that does reduce the chances of attacking some machines. However, a web server will still have ports 80 and 443 open and, if it isn't properly patched, will suffer in exactly the same way as if it wasn't behind NAT.
I'm not saying that you should tell everyone exactly how you have implemented your security, but you can't rely on secrecy to last. The important thing is to thoroughly test your security, preferably with an outside independent agency. This is particularly important if you want others to rely on your system and must include an audit of your code for software and settings for your hardware. Are customers more likely to trust an independent testing agency or a vendor trying to sell a product or system?
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