TippingPoint Zero Day Initiative

Apple Quicktime Font Table Signed Length Remote Code Execution Vulnerability

ZDI-11-340: December 7th, 2011


CVSS Score

Affected Vendors

Affected Products

TippingPoint™ IPS Customer Protection

TippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID 11876. For further product information on the TippingPoint IPS:

Vulnerability Details

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Apple Quicktime. 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 how the application parses font names embedded within an atom. When parsing the font name, the application will treat a length from the file as a signed value when copying font data into a buffer. Due to an unsigned promotion, this can be used to write outside the bounds of a buffer which can lead to code execution under the context of the application.

Vendor Response

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

Disclosure Timeline

    2011-07-20 - Vulnerability reported to vendor
    2011-12-07 - Coordinated public release of advisory


This vulnerability was discovered by:
    Luigi Auriemma