Cumulative Patch for Internet Explorer flawed
Microsoft Security Bulletin MS02-023 - Cumulative Patch for Internet Explorer released on 15 May 2002 was flawed. Yesterday, the bulletin was updated to correct erroneous information regarding attack vectors for the Cross-Site Scripting in Local HTML Resource and Script within Cookies Reading Cookies vulnerabilities and the capabilities of locally run scripts.
Microsoft Security Bulletin MS02-023 can be found here:
Updated Microsoft Security Bulletin is linked below the GreyMagic Software patch rant.
Microsoft released a cumulative patch yesterday, which, among other issues, allegedly patches the dialogArguments vulnerability (http://jscript.dk/adv/TL002/).
In their bulletin Microsoft makes several severe errors:
1. "A cross-site scripting vulnerability in a Local HTML Resource..."
No, Microsoft, the problem is not plain cross site scripting, the problem is that dialogArguments' security restrictions are bypassed and it is passed to the dialog even though it shouldn't. Please re-read the advisories.
2. "A successful attack requires that a user first click on a hyperlink. There is no way to automate an attack using this vulnerability."
This is simply wrong, the user doesn't have to click anything for this issue to be exploited, it can run automatically.
3. Microsoft also claims that this issue only exists in IE6.
Microsoft obviously doesn't follow Bugtraq. This issue also exists in IE5 and IE5.5, as we demonstrated in our GM#001-AX advisory.
In conclusion, Microsoft did not understand the problem. They only patched a symptom of this vulnerability, not its root cause.
As a result of that incomplete "patch" IE5 and IE5.5 are still very much vulnerable to this attack in other resources. For a demonstration see http://sec.greymagic.com/adv/gm001-ax/.
We hope that Microsoft fixes the actual issue this time, and not just the resource file.
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