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Controversy Surrounds Huge IE Hole
Suchetha wrote in with a Wired News bit talking about
security hole
in IE that allows malicious web pages to reformat a hard drive. The Wired
talks
more about bugtrack's handling of the whole thing, and how it essentially posted working
code for the exploit. Was it irresponsible or not?
Posting as Anon since I don't need the Karma:
n ee ring/issues/ie.shtml#opt
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Serious Internet Explorer Defect
This is a developing issue and the information presented here is preliminary in nature and subject to frequent changes. Last significant update - 11/08/02-1830
SUMMARY
A simple way to exploit an unfixed defect in Internet Explorer has been discovered that allows malicious web sites, and possibly malicious email messages read with Outlook or Outlook Express, to take control of a computer. All you would need to do is click a web link and the owner of the web site could take almost any action they desired on your computer.
Simple, working exploit software was recently published to a public mailing list.
There is no patch to fix the problem. Anti-virus and personal firewall software will not prevent an exploit. It is hoped that Microsoft will provide a patch to fix this defect in the near future.
It is impossible to predict how, when, or even if someone will take advantage of this but due to the ease with which bad things can be accomplished it was decided to post an announcement. Nothing at all may happen. Or someone could write a virus or put up a malicious web site to take advantage of the situation at any time. The last time a defect exploit with similar characteristics was published, it was quickly incorporated into many email viruses making it unnecessary to click an attachment to get infected.
The following practices are recommended for users of Internet Explorer, Outlook, and Outlook Express until more information becomes available:
1. Users of Outlook and Outlook Express should perform the following simple, unobtrusive procedure to disable scripts from executing in email messages:
Click the Tools menu item and select Options
Click the Security tab
In Outlook Express, make sure the Virus Protection security zone is set to Restricted site zone as shown in the window below:
In Outlook, make sure the Secure Content Zone is set to Restricted Sites as shown in the window below:
These are the default settings for Outlook 2002 and Outlook Express 6. Users of earlier versions should change the setting to Restricted.
2. Indiscriminate browsing of untrusted or questionable web sites should be avoided or scripting should be disabled as described in the additional security measures below. Note that hyper links sometimes appear in email or instant messages. If these messages are from malicious individuals, they could lead you to a malicious web site.
3. Indiscriminate clicking of hyper links in unexpected or suspect email messages, instant messages, and peer sharing resources should be avoided or scripting should be disabled in Internet Explorer as described in the additional security measures below.
ADDITIONAL SECURITY MEASURES AND INFORMATION
There is only one technical defense against an exploit at the present time and that is to disable scripting in Internet Explorer, Outlook, and Outlook Express. Instructions for disabling scripting in the mail clients were included in the recommendations above and should have little or no effect on day to day use.
Unfortunately, disabling scripting in Internet Explorer will adversely affect the operation of many web sites including E-campus and the Windows Update Site. There is, however, a way to specify trusted web sites that are are allowed to use scripting and disable it for all others. Users desiring to decrease risk may follow the instructions at the following web site under the section titled "Optional Internet Explorer Security Measures":
http://www.jmu.edu/computing/info-security/engi
Risk associated with this exploit and most others can be somewhat reduced by using a non-Administrative Windows account when browsing the web, reading email, and other day to day computer use.
The defect has been verified in Internet Explorer 5.5 and 6 SP1 running on Windows 98 and XP SP1 respectively. It is likely all varieties of 5.5 and 6 are vulnerable. A quick attempt on a Windows 95 computer running IE 5.0 was unsuccessful but not enough research was done to know why.
A possible symptom of an exploit is a Window similar to the one below suddenly appearing on your screen after clicking a hyperlink or opening an email message. The exact appearance of the Window may vary depending upon the version of Internet Explorer and operating system. Note that this window will appear if you click Help and under that circumstance the window appearance is not an indication of an exploit. If you are affiliated with James Madison University and see this window unexpectedly appear after clicking a web hyperlink or reading an email message, please contact Gary Flynn at x82364 ASAP. People affiliated with James Madison University can find my home number in the local directory and are encouraged to call me at home if such an event takes place after normal working hours.
The most sensible thing I've ever read about this kind of question is crptogram article last year by Bruce Schneier.
Prime numbers are exactly what Alan Greenspan says they are -S. Minsky
Ok, I expected that more people read bugtraq.. which is obviously not the case.
Their version of november is not actually the real november. From Andreas Sandblads mail:
"Microsoft was initially contacted 2002-10-04."
If you read Sandblad's actual BugTraq posting you will see that he had notified Microsoft more than a month before posting the details of the exploit. Quoting:
Microsoft was initially contacted 2002-10-04. After several mail exchanges, their final response were that the technique used to run programs with parameters from the "Local computer zone" was no security vulnerability. A fix should instead be applied for all possibilities for content in the "Internet zone" to access the "Local computer zone".
How much time does a company have to actually fix a problem this serious? When somebody takes the trouble to notify a company about a defect, they've already demonstrated helpfulness and responsibility. It would make sense for the company to take that helpful, responsible person into the loop, and at least update them periodically about what is being done about the problem. That would give a helpful person like Sandblad a basis for continuing to wait. In this case Microsoft gave no indication that they were doing anything about the problem or intended to do anything about it. Continuing to sit on the information certainly wouldn't give them any further incentive. Sandblad reported this problem, got a thanks-but-no-thanks, then after a month of no news went over their heads to the public. I would say he handled it very responsibly.
After reading the proof-of-concept script at http://online.securityfocus.com/archive/1/298748, I now know at least to avoid blind links.
Also, I've come up with this possible solution:
In IE, bring the potentially malicious page to the front, then press Ctrl-O to get the Open prompt. Enter this:
javascript:void(location.replace=null)
then click OK. Now anytime that a javascript on that page tries to do a location.replace command will now instead issue a null command (no command at all). (Assuming the script hasn't already been activated, under an onLoad event or something)
This works with annoying exit pop-up ads too:
javascript:void(window.onunload=null);
You can do this with all sorts of javascript commands that get abused. Find some offensive pages, look at their source, and disable the commands you see used often. (onunload is probably the worst and most often used).
Major inspiration from this cnet builder page.
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