Date: Tue, 11 May 1999 21:55:22 -0600 (MDT) From: cult hero To: InfoSec News Subject: [ISN] Everywhere your MAC address shows up Forwarded From: MICROSOFT'S HEAVY HAND IN THE COOKIE JAR A special report from YEOW - Barry Simon. See the Woody's Office Watch discussion and details on the Office 97 privacy problem. Issues 4.11 and 4.12 Because of the important Internet Explorer 5 coverage some regular WWW features have been held over to the next issue. We reported earlier on the brouhaha over the inclusion of hardware IDs in the Pentium III chip and privacy advocates' concerns about it. Turns out many of us already have hardware IDs on our systems since all Ethernet cards have a MAC (stands for 'Media Access Control', whatever that means!), a six byte ID number that networks need to be sure to properly direct network packets. Of course, the Pentium III ID's are more serious since many home systems don't (yet) have network cards and the biggest privacy concerns are in the consumer space. Due to wonderful sleuthing by Richard Smith of PharLap (who earlier located the April Fool's Bug discussed in WWW issue 2.2), the world has discovered a number of places that Microsoft has been using these MACs - in Windows 98 IDs, in Office 97 documents and in the microsoft.com cookies. And privacy concerns result from all these uses. To understand the issues, try a few experiments. First, you'll need your MAC assuming you have an Ethernet adapter. With Windows 9x, run the program winipcfg from the Run box. It should load with a dropdown that says 'PPP Adapter'. Change the dropdown to the name of your hardware adapter. The Adapter Address field will say something like 00-70-06-9A-8E-43. That's your MAC. Each byte is presented as two hex digits (0 through 9 or A-F) for a 12 character ASCII string which is what Microsoft uses. With Windows NT, run instead winmsd, go to the Network tab and pick Transports and you'll get the MAC. For the next experiment, you'll need to look at a Word 97 document in text mode. You can't do this with Word. If you have Quick View Plus (plain Quick View won't do), open a Word doc in QVP, go to the View menu and pick View as Text. Or make a small Word doc, save it and rename it to a .txt extension and open it in Notepad. Now search for the string PID. You should find _PID_ GUID and shortly afterwards, a long hex string inside braces such as {F96EB3B9-C9F1-11D2-95EB-0060089BB2DA}. Those 12 hex digits at the end will be your MAC. Yup, every Word doc, every Excel spreadsheet and every Power Point presentation is branded with an identifier showing the PC it came from. If your boss has a Word memo you sent her and a copy of the anonymous whistle blowing attachment you sent to the Feds, she could determine they were made on the same machine. (Of course, if you aren't careful, the document includes an author name and if any corrections were made, it may say who made the corrections. Within the next few days, Microsoft expects to post a white paper on all the 'metadata'; embedded in Office documents). To run the next experiments, you'll need Windows 98, so I'll tell you what happens so you can follow along in any event. In your Windows directory, you'll find a file called reginfo.txt. Open it in Notepad and look for a line called HWID; it ends with your MAC. This file is created when you install Windows and is transmitted to Microsoft when you register. And here's the clincher: even if you check the box not to send hardware information, this data is sent. And it's even worse - the data collection code is in an ActiveX control that can be used by any Internet site out there. Pharlap has a demo to illustrate this: go there and it displays your MAC on screen. Any site knowing of this control could track MACs of all Windows 98 visitors to their sites. There is also a demo and discussion at Windows Magazine. By the way, this ActiveX control is also in the Windows 2000 beta so if Microsoft hadn't been found out, NT users would have been hit next. Next, go to your cookies directory and open the text file whose name ends with microsoft.txt (it probably has a username@ in front where username is your login name). In it you'll find a string called GUID that includes your MAC (GUID, by the way, is short for Global Unique Identifier). This cookie is sent to www.microsoft.com every time you visit that site. You may have realized they were making a cookie when you registered at their site but I bet you didn't realize they were adding hardware information without your permission. (Actually the Win98 Registration Wizard made the cookie before you went to the Microsoft site.) You might want to search your Registry for your MAC as a string. I found mine numerous times - two in suspicious places viz a viz Microsoft. It's part of a key for Media Player called Client ID (is this passed on to the Media Player servers?) and as part of a key HKCU\Identities that seems to be connected with Outlook Express 5.0. There is certainly plenty here for the paranoid. Microsoft is collecting and storing in its databases unique hardware information. That information brands your documents, and is always sent on when you access Microsoft's site. One has to consider the possibility that Microsoft is keeping some master database tracking all sorts of interactions based on your MAC. And one has to allow the possibility that the MAC will be encoded in the information that is sent by the Office Registration Wizard in Office 2000. Microsoft has reacted vigorously to the developments in this story. They have two customer letters ( here and here) on their site in which they promise to remove the hardware ID part of the registration wizard in a Win98 upgrade. They also promise to delete 'any hardware ID information that may have been inadvertently gathered without the customer having chosen to provide Microsoft with this information.' Tools have already been posted to remove branding from Office applications and from already-created docs and there is a promise that branding will be removed >from the final version of Office 2000. Beyond these actions, there has been a full court spin operation. Some MS representatives have (unwisely in my opinion) attempted to minimize the issue. There have been claims that the doc branding was a part of a feature, never implement, intended solely to help network administrators. There has been harping on the fact that the MAC only identifies a machine but not an individual - true but not of much comfort in many cases. We've been told that Windows 98 sending a HWID even if you said not to send hardware information was a bug, not a feature - an inadvertent programming error. There's been no new statement about the use of MACs in cookies which I find most disturbing. We've been told by Microsoft representatives that the Office 2000 Registration Wizard doesn't collect MACs or anything like a MAC. Indeed, they claim that while the Office CD serial number can be reconstructed >from the 16 byte code sent by the wizard, the hardware info does not allow reconstruction. In particular, if the different CDs were used on the same machine, they'd be unable to tell that the codes came from the same machine. _____ The problem with the Microsoft position is that the company has so little credibility and there is too much of a pattern here. We pride ourselves on taking a middle road on Microsoft at Woody's newsletters. We don't hesitate to put their feet to the fire but, on the other hand, we don't take the position that Microsoft is the root of all evil and everything they say and do is two faced. That said, Woody's middle name isn't Polly and mine isn't Anna. Microsoft has amply demonstrated that it is company policy to, er, shade the truth when doing so serves a perceived business purpose. We see it in the leaked disinformation about Windows 2000 shipping this fall, we've seen it in their previous reactions to accusations and we saw it too often in the testimony at the DOJ trial. That means one has to take skeptically every statement that Microsoft has made about the MAC problem. I'm inclined to believe that branding of Office documents wasn't part of a plot to link together our entire lives in Microsoft's databases. But I'm insulted that they try to bat their eyelashes and claim to us that the sending of the HWID even when you told them not to send hardware info was an inadvertent error. And I'm concerned that we have no way of knowing that they've kept their promise to remove hardware IDs from their internal databases. Indeed, my presumption is that they will not. I worry that Microsoft is tucking all sorts of things into the holes they aren't discussing. While they have said they'll stop using HWID, they have also said they'll continue to use the MSID number which is created by the Windows 98 Registration wizard. And, guess what? As discovered by Peter Siering at the German publication C'T Magazine, the registration wizard also creates a Microsoft cookie that includes MSID. So even after the apologies and changes, it seems Microsoft will be quite capable of tracking us and linking online visits to registration information. It's interesting about credibility. There was also an Intel slip reported recently that they claimed was inadvertent. Apparently some mobile Pentium II's shipped with hardware IDs even though these were only announced for Pentium III's. Intel's explanation is that they experimented with this feature in the manufacturing process for the mobile Pentium II but it was supposed to be disabled before shipping. One line inadvertently didn't do the disabling. Intel's credibility is such that I'm willing to accept their claim of inadvertence here. -o- Subscribe: mail majordomo@repsec.com with "subscribe isn". Today's ISN Sponsor: Hacker News Network [www.hackernews.com]