ZDI-06-026: Microsoft Internet Explorer Multiple CSS Imports Memory
August 8, 2006
-- CVE ID:
-- Affected Vendor:
-- Affected Products:
Internet Explorer 6 All Versions
Internet Explorer 5 SP4
-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability since August 8, 2006 by Digital Vaccine protection
filter ID 4606. For further product information on the TippingPoint IPS:
-- Vulnerability Details:
This vulnerability allows attackers to execute arbitrary code on
vulnerable installations of Microsoft Internet Explorer. User
interaction is required to exploit this vulnerability in that the
target must visit a malicious page.
The specific flaw exists due to improper garbage collection when
multiple "imports" are used on a "styleSheets" collection. Crafting a
long chain of CSS imports in an HTML document results in a memory
corruption eventually leading to code execution.
-- Vendor Response:
Microsoft has issued an update to correct this vulnerability. More
details can be found at:
-- Disclosure Timeline:
2006.06.14 - Vulnerability reported to vendor
2006.08.08 - Digital Vaccine released to TippingPoint customers
2006.08.08 - Coordinated public release of advisory
This vulnerability was discovered by Sam Thomas.
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Instead, upon notifying the affected product vendor, 3Com provides its
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vulnerability are not exposed to any parties until an official vendor
patch is publicly available. Furthermore, with the altruistic aim of
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who have a vulnerability protection or mitigation product.