LinkedIn Password Leak – Whose Interests Are Being Served?

As I’m sure most of you have heard, there is a LinkedIn password breach going on. As breaches continue to happen, they seem to move faster and faster. Within 24 hours of the breach occurring, 60% of over six million passwords were cracked. Since people are also reading blogs more quickly these days, I’ll leap straight into what you need to do. Then, you’re still interested, keep reading for a bit of analysis.

• Change your LinkedIn password to something random, long and complex… at least 20 characters.
• Do not use this password anywhere else.
• If you don’t remember these sorts of passwords easily, use a tool like KeePass, LastPass or 1Password.
• If you are responsible for the security of others, get them to change their passwords too.

That’s it.

Now, let’s look at what happened. First of all, a set of six million encrypted passwords appeared within the attacker community and help was asked for in cracking them. Now, the passwords are referred to as unsalted SHA1. This means that, while the passwords were encrypted using a reasonable algorithm, they were not salted. This means they are much easier to crack and this explains the speed with which they were found out.

The passwords were posted without email addresses. However, it is not reasonable to assume that malicious attackers would ask for help cracking passwords that they couldn’t use, so it is very likely that they have this information. They may well also have a pile of passwords that were NOT posted because they had already cracked those passwords. So, understanding these facets of the attacker community, let’s look at LinkedIn’s response.

• Members that have accounts associated with the compromised passwords will notice that their LinkedIn account password is no longer valid.
• These members will also receive an email from LinkedIn with instructions on how to reset their passwords. There will not be any links in this email. Once you follow this step and request password assistance, then you will receive an email from LinkedIn with a password reset link.
• These affected members will receive a second email from our Customer Support team providing a bit more context on this situation and why they are being asked to change their passwords.
  

On the face of it, this is reasonable. After all, if LinkedIn sent you an email with a password reset link, it’d look a whole lot similar to a fraudulent email with a password stealing link. So, props to LinkedIn for thinking this through.

However, there is still the matter of trust.

See, the key to this whole response is “Members that have accounts associated with the compromised passwords”. This concerns me as it implies that LinkedIn pulled encrypted passwords from their database and compared them to the PUBLIC breach data. This is will necesarilly miss any accounts that the attackers have not released. This could be accounts with simple passwords or particularly sensitive accounts. Suppose they filtered out all accounts that started as “ceo@” or “president@”. Intelligent criminals would want to keep those sorts of accounts to themselves, even if they took a while longer to crack.

One of the core rules of dealing with a data breach is that if you don’t know how it happened and can prove that it only affected a limited number of accounts, you must assume that they are compromised. In this case, a better security response would be to put information about the breach on the front page. At this time, there’s nothing there. Once I log in, though, there is a tiny link under “LinkedIn Today” that references an article on CNN about the breach. Basically, there is nothing prominent or official other than their blog… which you must be following to notice.

The response that I would like to see would involve the following pieces:

• Information as to what happened and what LinkedIn is doing to prevent a recurrence.
• Information about how to select a good password and change it on the system.
• This information sent out via email, posted on the blog and highlighted after logging in to the system.

Instead, the best we get is this advice, which is inadequate. Let’s pick this apart. The original is in italics. My commentary will be in bold.

Changing Your Password:

• Never change your password by following a link in an email that you did not request, since those links might be compromised and redirect you to the wrong place.
  
• I agree with this.
  
• You can change your password from the LinkedIn Settings page. 
• If your account has been compromised, you should be locked out and unable to access the Settings page. They should direct people to the next bullet instead.
  
• If you don’t remember your password, you can get password help by clicking on the Forgot password? link on the Sign in page.
• This is good, as it requires any password to involve an out-of-band mechanism like access to your email account.
• In order for passwords to be effective, you should aim to update your online account passwords every few months or at least once a quarter.
• Bad bad bad! Needing to change passwords frequently implies poor security on the part of the administrators. If they are monitoring their systems and capable of knowing when an event occurs, they will tell you when to change your password. People that are forced to frequently change passwords tend to select weaker passwords and use them on more sites. This means that if ANY site is breached, ALL accounts are placed at risk. This is probably the worst advice they give.

Creating a Strong Password:

• Variety – Don’t use the same password on all the sites you visit.
• Good. Also, don’t use the same base. For example, if you pick “password123” as a base, and your LinkedIn password was “password123LI”, it’s not a big stretch to “password123FB” for Facebook or “password123WF” for Wells Fargo.
• Don’t use a word from the dictionary.
• I think we put too much emphasis on this. The fact is that the dictionaries we use in the security world are very different from your average Mirriam Websters or OED.
• Length – Select strong passwords that can’t easily be guessed with 10 or more characters.
• I think that 10 is too short. I say 20 above. Most of mine are over 30. The longer the password, the more time you have to deal with resets in the event of a breach.
• Think of a meaningful phrase, song or quote and turn it into a complex password using the first letter of each word.
• Passphrases are good… completely random strings are better. I like to use passphrases to access my password wallets, and the wallets to store the real passwords.
• Complexity – Randomly add capital letters, punctuation or symbols.
• I agree with the general intent here, but humans are bad at randomness. Let a computer generate your passwords and you’ll be a lot better off.
• Substitute numbers for letters that look similar (for example, substitute “0″ for “o” or “3″ for “E”.
• Bad advice. Most attacker dictionaries include these substitutions so it only makes things more difficult for you.
• Never give your password to others or write it down.
• Well, never give your password to others anyway. If you can’t remember a good password, write it down.  Just store the paper in a secure place… like a safe. Better yet, store it in a password wallet system that keeps the datafile in a digital “safe”, properly encrypted and away from prying eyes.

A few other account security and privacy best practices to keep in mind are:

• Sign out of your account after you use a publicly shared computer.
• You know what would be better? “Don’t sign into your account from a public computer.”
• Manage your account information and privacy settings from the Profile and Account sections of your Settings page.
• If you understand the privacy settings in each social media system you use, give yourself a gold star. Might be better if sites like LinkedIn had secure defaults and users could choose to weaken them.
• Keep your antivirus software up to date.
• Yes, because of all the LinkedIn viruses we see running amok. This is like a car company issuing a brake recall with the advice “remember to only drive on roads”. The truth is that anti-malware systems are needed because our operating system and application vendors have failed in their jobs. It’s not LinkedIn’s fault, but the advice doesn’t really belong here either.
• Don’t put your email address, address or phone number in your profile’s Summary.
• Really?  I mean, REALLY?  Isn’t the whole point of LinkedIn to share your contact information with others? Hmm… perhaps LinkedIn’s stock does better if people only contact one another through LinkedIn’s “mail” system. Then again, perhaps more people would use that system if it worked more reliably. Perhaps I’m editorializing a bit more than I should be. ;)
• Only connect to people you know and trust.
• This is interesting advice, given that many people use LinkedIn to meet new people and get new opportunities. LinkedIn offers very little to people that would actually follow this rule, as if you already know and trust someone, you already have their contact information. LinkedIn never really took off as a content platform like MySpace, Facebook or even Google+. Everyone knows that no one is going to follow this advice.  Besides, the greater risk here is leaking your personal information to someone you “know and trust” whose account has been compromised. This is a case for a security tradeoff and careful consideration of what you share. A blind prohibition is not useful.
• Report any privacy issues to Customer Service.
• Here’s a bit of advice. Only refer people to your customer service when you know it’s good.  Just sayin’.

Basically, what we have here is a situation where LinkedIn has strong incentives to downplay the issue. They look bad already, so the smaller and less significant the breach, the less immediate damage they face. They also very much do not want the world to seriously consider the weigh the risks of sharing their personal information via the Internet. After all, the entire business model of social media is riskier than we’d like to think. The sooner everyone figures this out, the less money the owners make and the more people in the industry lose their jobs.

This is in direct conflict with that the users (or product) of LinkedIn need. We need to be able to trust the people we give our information to. We need to know that they are doing what they should, investing in good technology, people and processes and being forthright with us as to what is going on. We need a partner that communicates with us with our own needs in mind, not just their own.

When one person is best served with honesty and the person they are talking to is best served by lying, there are going to be problems. Consider this in the wake of any breach, whatever side you land on. The long term future of any relationship in conflict is less than rosy.