Employee Resisitance to New Controls

One of the reasons that our security is as bad as it is, is the perceived resistance of employees to new, or even changed, controls.  Why is it that even enterprises that offer strong authentication to customers, still rely upon fraudulently reusable passwords, vulnerable to social engineering, for employee authentication?  Employees continue to rely upon passwords even though they are implicated in more than half of all breaches and even though msny strong authentication solutions are much more convenient than passwords.  Could it be, at least in part, that management wants to avoid the inevitable employee whining that accompanies any and every change in controls?

Its true!  Many, not to say most, employees do whine and complain over any change in controls.  Even good managers are deterred from such changes by such resistance.  The good news is that most of the resistance only lasts a day or two.  Even those who complained the earliest and loudest get over it in a day or two.  They do not continue to resist what they quickly come to see as inevitable.  

Oh its true, a few continue to complain.  Let's face it, they were not happy yesterday, they will not be happy tomorrow, their happiness is not within management's control. They are grievance collectors, Failing to do the right thing in an attempt to quiet their complaints is futile.  Get over it.  Do the right thing.  

The Biden Executive Order

There is nothing like long lines at the gas pumps to get the attention of government.  This is an initiative that is long overdue.  There is a great deal to do.  Cyber is the infrastructure that we use to operate all the others, particularly to include energy and finance, and it is all too fragile and porous for the reliance that we have upon it.  

It is good to see that "zero trust" made the list.  The concept goes back to the mainframe and many of us have been actively promoting it for the internet for years.  It is important to use it both horizontally, that is system to system and service to service, and vertically, through the layers of the application.  

Zero Trust requires strong authentication (at least two kinds of evidence, at least one of which is resistant to replay) both user to system and process to process.  One cannot trust a process whose identity is not reliable.  If strong authentication is not the single most effective and efficient measure at our disposal, it is certainly among the top three.  It deserves its own mention.  

Zero trust also implies resistance to lateral compromise within the enterprise.  It should not be possible to compromise an entire enterprise simply by getting one user to click on a bait message in an e-mail or on a web-site.  In addition to resistance to fraudulent credential replay, we need structured networks.  I would like to see end-to-end application-layer encryption but, at least in the short run, I would settle for network segmentation and layering.  

I am glad that it addresses software quality.  However, the practice here is so shoddy and the contributors so many that simply saying we will address it through government purchasing power will not be enough.  Nor can we rely on training alone.  We need systems and development processes that make it much easier to do it right than to do it wrong.  

I would like to have seen the order address accountability and transparency for privileged users.  Edward Snowden should not have been able to run rampant through a network that one would have expected to be "secure."  It is ironic that the place that we are most likely to see shared credentials is among privileged users.  Wherever there are two or more privileged users per shift, we need privileged access policy and management systems.  

We cannot continue to allow just any amateur to connect anything they like to the public networks.  While it may require legislation, we must require that only mechanisms built by professionals to infrastructure standards (e.g., built for the ages, fails in an orderly and safe manner, resistant to easily anticipated misuse and abuse) can attach directly to the public networks.  As we need structure networks within the enterprise, we need structure within the Internet.  

We also need to have accountability for suppliers who distribute (malicious) code that they did not write.  This too may require legislation but a class action suit against SolarWinds would be a start.  

The Biden Executive Order is a start but only a start.  There is much to do.  Let us get on with it.

SolarWinds

By now most should realize that SolarWinds is a compromise on an almost unimaginable scale. It is a crisis.  While there are "indicators of compromise" there are no indicators of all compromises.  While the attackers have concentrated on gathering intelligence on only a small number of target sites, all SolarWinds customers must assume that they are compromised and that there may be multiple backdoors into their systems for which there are no ICUs.  Only a small number of enterprises, perhaps none, have sufficient control over the content of their systems to be sure that they are resistant to such backdoors.

In https://us-cert.cisa.gov/ncas/alerts/aa20-352a DHS/CISA has suggested that some enterprises under some circumstances will have to "rebuild (from scratch) hosts monitored by the SolarWinds Orion monitoring software using trusted sources."  In fact, we may have to rebuild all enterprise systems.  

President Obama's chief of staff, Rahm Emanuel, famously said in 2008, “You never want a serious crisis to go to waste. I mean, it's an opportunity to do things that you think you could not do before.”  It would be tragic, if after rebuilding our systems, we should come away as vulnerable as when we started.  

We should take Rahm's "opportunity" to introduce "zero trust," indeed zero trust on steroids.  One might well start with a Software Defined Network.  One should include mutually suspicious processes, strong authentication at all levels, and "least privilege" access control.  

Rebuilding systems in month's that took decades to evolve is a daunting task.  I am reminded of what my father taught me when I was just starting out in IT almost sixty years ago.  "Son," he said, "all hard problems in information technology have one and the same answer: one application at a time."  We can do this.  We should use the crisis to overcome the inertia that has kept us from doing what we all know we should have done a while ago.  We know what to do: all we need is the leadership to do it.  

Do not worry about the cost.  Much of what we need to do, we can do with available resources.  For example, we can implement "least privilege" with available tools.  It only requires a change in intent.  In any case, there is always enough money to do that which must be done.  

Limitations of Biometrics

It is Blackhat/Defcon time so it should not surprise anyone that the media is full of hacks. While the hackers pretend to demonstrate that the security mechanism is useless, most of the attacks are so expensive as to be impractical.  What they really demonstrate is the limitations of the mechanism.  Regular readers of this blog know that all security mechanisms have limitations; understanding those limitations are part of our stock in trade and I write about them often.   

A recent demonstration spoofed Apple's FaceID in only "120 seconds," as though that were the only cost of attack.  They omitted the special knowledge and access.  A recent article in BankInfoSecurityNews raised alarms over the discovery of a database of fingerprint images for sale.  

First, keep in mind that biometrics are really about convenience, not security. That is why they are best used as one factor in multi-factor systems. 

Second, they do not rely upon the secrecy of the reference but upon their resistance, at least in context, to counterfeiting. Your visage is an authenticator for your drivers license. It is public information. While a photograph of you might be able to fool a computer, no other person would be likely to confuse the photo with you.  There is too little information in the photo for it to be mistaken for you.  The more information that the implementation uses, the lower the risk of false positives but the higher that of false negatives and the more power and time required for a check.  

Finally, as this article suggests, just like passwords, biometrics are fundamentally vulnerable to spoofing and replay attacks; implementations must resist them. For example, Apple's FaceID uses tests of "liveness" to distinguish between a real person and a photo of the person or a replay of an earlier submission.  Perhaps they are better used on mobiles, where possesion of the mobile is one factor and where the instant data is compared to the reference locally and does not go across a network where it could be captured for replay.  

Limitations of Two Factor Authentication

In an opinion piece in the New York Times, Professor Josephine Wolff of Rochester Institute of Technology describes a “phishing” attack in which two factor authentication might not protect you.  The bait asks you to click on it to go to an application that you are authorized to use.  Clicking on the link takes you to a site that mimics the application.  It mimics the prompts for the user ID, the password, and the one-time password, all three of which it uses to logon to the real application in your name.  Unfortunately, to some readers this may read like a general limitation of two factor authentication rather than a special case.  Some users might conclude that two factor authentication is not worth the inconvenience.  

Consider some of the conditions for the success of this attack.  First the bait must be for an application to which you actually have an account.  Second, the bait must be sufficiently well crafted to convince you that you want to respond.  Third, you must respond, not by going to the application the way you usually do but by clicking on the bait.  Of course, this is very bad practice.  

While if this man-in-the-middle attack is sufficiently well designed as to fool you, it has only stolen a session that you started. Unlike simple passwords it cannot be use to initiate a session on its own.  It has not exposed you to fraudulent reuse of your credentials.  It cannot be used to compromise other systems “laterally” within the enterprise.  

Well designed applications will not permit the attacker to turn off the two factor authentication without requiring a second one time password and will confirm any such change out of band.    

This is not the only possible successful attack against two factor, depending upon the implementation.  Consider Google’s implementation.   It offers the user five different choices of how to get the one-time password (OTP), in an SMS text message, in an e-mail message, in spoken language over the phone, from a software generator, or from a hardware token (Google Titan).  All of these must ensure that the OTP come from and get to the right place.

For example, SMS text and voice over the phone rely upon legitimate user’s control of the phone number.  E-mail requires that the OTP be sent to the legitimate user’s address.  Attackers have been successful in duping the carrier support personnel into pointing the the number to a new SIM or phone that they control.  They have also been successful in duping the application support personnel to change the number, or e-mail address to which they send the one time password.  Good practice requires that the change be confirmed out of band.  After compromise the user will not get one time passwords, or perhaps even phone calls, that they are expecting.   

Even software and hardware tokens rely upon the right token being associated with the legitimate user.  In order to compensate for lost or broken tokens, most applications provide for enrolling new tokens.  An attacker might succeed in duping support personnel into enrolling their token in place of the one heldby the legitimate user.  

Note that all of these attacks require work and special knowledge.  None of them guarantees success, none of them scales well.  Those that permit fraudulent reuse, also deny the legitimate user access and should be obvious.  

Two factor authentication using one time passwords is a special case of “strong authentication,” defined as multiple forms of evidence at least one of which (e.g., one time passwords) is resistant to replay.  Note that security can be increased by using more forms of evidence.  This at the expense of convenience.  

Strong authentication should be preferred for most applications.  Simple passwords must be used only for trivial applications.  All security mechanisms have limitations that we must understand and compensate for but that does not make them unuseable.  We must not permit the perfect to become the enemy of the good.  

The Use of SMS for Strong Authentication

NIST and others have discouraged the use of SMS for strong authentication.  This is another case of the perfect as the enemy of the good. 

First, strong authentication using a one time password sent via SMS is dramatically more secure than a replayable password. Second, if you get a one-time password when you ask for it, you are safe.

The problem is not so much with SMS but with the (cell) phone number. There is a risk that an attacker can either change the number in your account, to which the one time password will be sent, to a number other than yours, or get the phone company to associate, re-assign, your number with their phone. In either case, you will not get the one time password when you ask for it. In the latter case, you will not even get phone calls. Whenever the cell phone number in your profile is changed, you will get an e-mail message asking you if you really did it.

Carriers have controls in place to resist fraudulent reassignment of numbers to new phones.  However, the large number of agents and their desire to be accommodating, makes them vulnerable to ”social engineering” attacks. 

The difference in risk between a one-time password sent to your phone and one generated on board is small, particularly when compared to the difference in risk between either and a reuseable password.

In certain circumstances, the difference in convenience may be great. I have ten different accounts associated with my cell phone number. If I get a new phone, all my accounts continue to work as they did on the old phone. The number has moved to the new phone. If I used an on-board password generator, not portable to the new phone, I would have to register the new password generator with each of the ten accounts. I have to do that by calling support, authenticating myself, and registering the new generator. Until I have done that, I cannot logon to or use the account.

If you think about it, the real risk is in provisioning of the phone number or the registering of the on board generator (e.g., VIP Access, Google Authenticator, RSA SecurID Software Token).