TippingPoint Zero Day Initiative
 

Microsoft Internet Explorer EOT File hdmx Parsing Remote Code Execution Vulnerability

ZDI-10-198: October 12th, 2010

CVE ID

CVSS Score

Affected Vendors

Affected Products

TippingPoint™ IPS Customer Protection

TippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID 4062. For further product information on the TippingPoint IPS:

Vulnerability Details

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Microsoft Windows. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.

The specific flaw exists within the conversion of an Embedded OpenType file to TrueType format within t2embed.dll. The most likely vector for this to be exploited is via Internet Explorer as an embedded font in an HTML/CSS document. The flaw itself is due to an integer overflow when parsing hdmx records. A record size and record count variable are trusted and operated upon. The resulting value is used in a copy loop that can be manipulated to corrupt memory. This can be abused by an attacker to execute remote code under the context of the user running the browser.

Vendor Response

Microsoft has issued an update to correct this vulnerability. More details can be found at:

Disclosure Timeline

    2010-06-23 - Vulnerability reported to vendor
    2010-10-12 - Coordinated public release of advisory

Credit

This vulnerability was discovered by:
    Sebastian Apelt (www.siberas.de)