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I told you so

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[tags]Windows, Office, malware, vulnerabilities[/tags]

This appeared in USA Today yesterday: Cyberspies exploit Microsoft Office.  This is yet more support for my earlier post.

So, are you ready to join the movement—stop sending Word documents in email?

Update 4/28: And here is yet another story of how Word files are being used against victims.

[posted with ecto]

What security push?

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[tags]Vista, Windows, security,flaws,Microsoft[/tags]

Update: additions added 4/19 and 4/24, at the end.

Back in 2002, Microsoft performed a “security standdown” that Bill Gates publicly stated cost the company over $100 million.  That extreme measure was taken because of numerous security flaws popping up in Microsoft products, steadily chipping away at MS’s reputation, customer safety, and internal resources.  (I was told by one MS staffer that response to major security flaws often cost close to $1 million each for staff time, product changes, customer response, etc.  I don’t know if that is true, but the reality certainly was/is a substantial number.)

Without a doubt, people inside Microsoft took the issue seriously.  They put all their personnel through a security course, invested heavily in new testing technologies, and even went so far as to convene an advisory board of outside experts (the TCAAB)—including some who have not always been favorably disposed towards MS security efforts.  Security of the Microsoft code base suddenly became a Very Big Deal.

Fast forward 5 years: When Vista was released a few months ago, we saw lots of announcements that it was the most secure version of Windows ever, but that metric was not otherwise qualified; a cynic might comment that such an achievement would not be difficult.  The user population has become habituated to the monthly release of security patches for existing products, with the occasional emergency patch.  Bundling all the patches together undoubtedly helps reduce the overhead in producing them, but also serves to obscure how many different flaws are contained inside each patch set.  The number of flaws maybe hasn’t really decreased all that much from years ago.

Meanwhile, reports from inside MS indicate that there was no comprehensive testing of personnel to see how the security training worked and no follow-on training.  The code base for new products has continued to grow, thus opening new possibilities for flaws and misconfiguration.  The academic advisory board may still exist, but I can’t find a recent mention of it on the Microsoft web pages, and some of the people I know who were on it (myself included) were dismissed over a year ago.  The external research program at MSR that connected with academic institutions doing information security research seems to have largely evaporated—the WWW page for the effort lists John Spencer as contact, and he retired from Microsoft last year.  The upcoming Microsoft Research Faculty Summit has 9 research tracks, and none of them are in security.

Microsoft seems to project the attitude that they have solved the security problem.

If that’s so, why are we still seeing significant security flaws appear that not only affect their old software, but their new software written under the new, extra special security regime, such as Vista and Longhorn?  Examples such as the ANI flaw and the recent DNS flaw are both glaring examples of major problems that shouldn’t have been in the current code: the ANI flaw is very similar to a years-old flaw that was already known inside Microsoft, and the DNS flaw is another buffer overflow!!  There are even reports that there may be dozens (or hundreds) of patches awaiting distribution for Vista.

Undoubtedly, the $100 million spent back in 2002 was worth something—the code quality has definitely improved.  There is greater awareness inside Microsoft about security and privacy issues.  I also know for a fact that there are a lot of bright, talented and very motivated people inside Microsoft who care about these issues.  But questions remain: did Microsoft get its money’s worth?  Did it invest wisely and if so, why are we still seeing so many (and so many silly) security flaws?  Why does it seem that security is no longer a priority?  What does that portend for Vista, Longhorn, and Office 2007?  (And if you read the “standdown” article, one wonders also about Mr. Nash’s posterior. grin )

I have great respect for many of the things Microsoft has done, and admiration for many of the people who work there.  I simply wish they had some upper management who would realize that security (and privacy) are ongoing process needs, not one-time problems to overcome with a “campaign.”

What do you think?

[posted with ecto]

Update 4/19: The TCAAB does still continue to exist, apparently, but with a greater focus on privacy issues than security.  I do not know who the current members might be.

Update 4/24: I have heard (informally) from someone inside Microsoft in informal response to this post.  He pointed out several issues that I think are valid and deserve airing here;

  1. Security training of personnel is on-going.  It still is unclear to me whether they are employing good educational methods, including follow-up testing, to optimize their instruction.
  2. The TCABB does indeed continue (and was meeting when I made the original post!).  It has undergone some changes since it was announced, but is largely the same as when it was formed.  What they are doing, and what effect they are having (if any), is unclear.
  3. Microsoft’s patch process is much smoother now, and bundled patches are easier to apply than lots of individual ones.  (However, there are still a lot of patches for things that shouldn’t be in the code.)
  4. The loss of outreach to academia by MSR does not imply they aren’t still doing research in security issues.

Many of my questions still remain unanswered, including Mr. Nash’s condition….

Insecure when run on Vista, thanks to symbolic links

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I was surprised to learn a few weeks ago that Vista added symlink support to Windows.  Whereas I found people rejoicing at the new feature, I anticipate with dread a number of vulnerability announcements in products that worked fine under XP but are now insecure in the presence of symlinks in the file system.  This should continue for some time still, as Windows programmers may take time to become familiar with the security issues that symlinks pose.  For example, in the CreateFile function call, “If FILE_FLAG_REPARSE_POINT is not specified and:

  * If an existing file is opened and it is a symbolic link, the handle returned is a handle to the target.
  * If CREATE_ALWAYS, TRUNCATE_EXISTING, or FILE_FLAG_DELETE_ON_CLOSE are specified, the file affected is the target.”
(reference:  MSDN, Symbolic link effects on File system functions, at:  http://msdn2.microsoft.com/en-au/library/aa365682.aspx)

So, unless developers update their code to use that flag, their applications may suddenly operate on unintended files.  Granted, the intent of symbolic links is to be transparent to applications, and being aware of symbolic links is not something every application needs.  However, secure Windows applications (such as software installers and administrative tools) will now need to be ever more careful about race conditions that could enable an attacker to unexpectedly create symlinks.  They will also need to be more careful about relinquishing elevated privileges as often as possible. 

In addition, it is easy to imagine security problems due to traps planted for administrators and special users, to trick them into overwriting unintended files.  UNIX administrators will be familiar with these issues, but now Windows administrators may learn painful lessons as well. 

Hopefully, this will be just a temporary problem that will mostly disappear as developers and administrators adjust to this new attack vector.  The questions are how quickly and how many vulnerabilities and incidents will happen in the meantime.  One thing seems certain to me:  MITRE’s CWE will have to add a category for that under “Windows Path Link problems”, ID 63.

On standard configurations

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[tags]monocultures, compliance, standard configurations, desktops, OMB[/tags]

Another set of news items, and another set of “nyah nyah” emails to me.  This time, the press has been covering a memo out of the OMB directing all Federal agencies to adopt a mandatory baseline configuration for Windows machines.  My correspondents have misinterpreted the import of this announcement to mean that the government is mandating a standard implementation of Windows on all Federal machines.  To the contrary, it is mandating a baseline security configuration for only those machines that are running Windows.  Other systems can still be used (and should be).

What’s the difference? Quite a bit. The OMB memo is about ensuring that a standard, secure baseline is the norm on any machine running Windows.  This is because there are so many possible configuration options that can be set (and set poorly for secure operation), and because there are so many security add-ons, it has not been uncommon for attacks to occur because of weak configurations.  As noted in the memo, the Air Force pioneered some work in decreeing security baseline configurations.  By requiring that certain minimum security configuration settings were in place on every Windows machines, there was a reduction in incidents.

From this, and other studies, including some great work at NIST to articulate useful policies, we get the OMB memo.

This is actually an excellent idea.  Unfortunately, the minimum is perhaps a bit too “minimum.”  For instance, replacing IE 6 under XP with Firefox would probably be a step up in security.  However, to support common applications and uses, the mandated configuration can only go so far without requiring lots of extra (costly) work or simply breaking things.  And if too many things get broken, people will find ways around the secure configuration—after all, they need to get their work done!  (This is often overlooked by novice managers focused on “fixing” security.)

Considering the historical problems with Linux and some other systems, and the complexity of their configuration, minimum configurations for those platforms might not be a bad idea, either.  However, they are not yet used in large enough numbers to prompt such a policy.  Any mechanism or configuration where the complexity is beyond the ken of the average user should have a set, minimum, safe configuration. 

Note my use of the term “minimum” repeatedly.  If the people in charge of enforcing this new policy prevent clueful people from setting stronger configurations, then that is a huge problem.  Furthermore, if there are no provisions for understanding when the minimum configuration might lead to weakness or problems and needs to be changed, that would also be awful.  As with any policy, implementation can be good or be terrible.

Of course, mandating the use of Windows (2000, XP, Vista or otherwise) on all desktops would not be a good idea for anyone other than Microsoft and those who know no other system.  In fact, mandating the use of ANY OS would be a bad idea.  Promoting diversity and heterogeneity is valuable for many reasons, not least of which are:

  1. limit the damage possible from attacks targeting a new or unpatched vulnerability
  2. limit the damage possible from a planted vulnerability
  3. limit the spread of automated attacks (malware)
  4. increase likelihood of detection of attacks of all kinds
  5. provide incentive in the marketplace for competition and innovation among vendors & solutions
  6. enhance capability to quickly switch to another platform in the event a vendor takes a turn harmful to local interests
  7. encourages innovation and competition in design and structure of 3rd-party solutions
  8. support agility—allow testing and use of new tools and technologies that may be developed for other platforms

These advantages are not offset by savings in training or bulk purchasing, as some people would claim.  They are 2nd order effects and difficult to measure directly, but their absence is noted….usually too late.

But what about interoperability?  That is where standards and market pressure come to bear.  If we have a heterogeneous environment, then the market should help ensure that standards are developed and adhered to so as to support different solutions.  That supports competition, which is good for the consumer and the marketplace.

And security with innovation and choice should really be the minimum configuration we all seek.

[posted with ecto]

Surprise, Microsoft Listed as Most Secure OS

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It is well-known that I am a long-time user of Apple Macintosh computers, and I am very leery of Microsoft Windows and Linux because of the many security problems that continue to plague them.  (However, I use Windows, and Linux, and Solaris, and a number of other systems for some things—I believe in using the right tool for each task.)  Thus, it is perhaps no surprise that a few people have written to me with a “Nyah, nyah” message after reading a recent article claiming that Windows is the most secure OS over the last six months. However, any such attitude evidences a certain lack of knowledge of statistics, history, and the underlying Symantec report itself.  It is possible to lie with statistics—or, at the least, be significantly misled, if one is not careful.

First of all, the news article reported that —in the reporting period—Microsoft software had 12 serious vulnerabilities plus another 27 less serious vulnerabilities.  This was compared with 1 serious vulnerability in Apple software out of a total of 43 vulnerabilities.  To say that this confirms the point because there were fewer vulnerabilities reported in MS software (39 vs. 43) without noting the difference in severity is clearly misleading.  After all, there were 12 times as many severe vulnerabilities in MS software as in Apple software (and more than in some or all of the others systems, too—see the full report).

Imagine reading a report in the newspaper on crime statistics.  The report says that Portland saw one killing and 42 instances of littering, while Detroit had 27 instances of jaywalking and 12 instances of rape and homicide.  If the reporter concluded that Detroit was the safer place to live and work, would you agree?  Where do you think you would feel safer?  Where would you be safer (assuming the population sizes were similar; in reality, Portland is about 2/3 the population of Detroit)?

More from a stochastic point of view, if we assume that the identification of flaws is more or less a random process with some independence, then it is not surprising if there are intervals where the relative performance in that period does not match the overall behavior.  So, we should not jump to overall conclusions when there are one or two observational periods where one system dominates another in contrast to previous behavior.  Any critical decisions we might wish to make about quality and safety should be based on a longer baseline; in this case, the Microsoft products continue to be poor compared to some other systems, including Apple.  We might also want to factor in the size of the exposed population, the actual amount of damages and other such issues.

By analogy, imagine you are betting on horses.  One horse you have been tracking, named Redmond, has not been performing well.  In nearly every race that horse has come in at or below the middle of the pack, and often comes in last, despite being a crowd favorite.  The horse looks good, and lots of people bet on it, but it never wins.  Then, one day, in a close heat, Redmond wins!  In a solid but unexciting race, Redmond comes in ahead of multiple-race winner #2 (Cupertino) by a stride.  Some long-time bettors crow about the victory, and say they knew that Remond was the champ.  So, you have money to gamble with.  Are you going to bet on Redmond to win or place in each of the next 5 races?

Last of all, I could not find a spot in the actual Symantec report where it was stated that any one system is more secure than another—that is something stated by the reporter (Andy Patrizio) who wrote the article.  Any claim that ANY system with critical flaws is “secure” or “more secure” is an abuse of the term.  That is akin to saying that a cocktail with only one poison is more “healthful” than a cocktail with six poisons.  Both are lethal, and neither is healthful under any sane interpretation of the words.

So, in conclusion, let me note that any serious flaws reported are not a good thing, and none of the vendors listed (and there are more than simply Microsoft and Apple) should take pride in the stated results.  I also want to note that although I would not necessarily pick a MS platform for an application environment where I have a strong need for security, neither would I automatically veto it.  Properly configure and protect any system and it may be a good candidate in a medium or low threat environment. As well, the people at Microsoft are certainly devoting lots of resources to try to make their products better (although I think they are trapped by some very poor choices made in the past).

Dr. Dan Geer made a riveting and thought-provoking presentation on cyber security trends and statistics as the closing keynote address of this year’s annual CERIAS Security Symposium.  His presentation materials will shortly be linked into the symposium WWW site, and a video of his talk is here.  I recommend that you check that out as additional material, if you are interested in the topic.