TippingPoint Zero Day Initiative
 

Microsoft Office Excel Binary Worksheet Use-After-Free Remote Code Execution Vulnerability

ZDI-15-546: November 10th, 2015

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 20833. For further product information on the TippingPoint IPS:

Vulnerability Details


This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Microsoft Office Excel. 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 handling of binary Excel files (.xlsb). By providing a malformed file, an attacker can cause a pointer to be re-used after it has been freed. An attacker could leverage this to execute arbitrary code under the context of the current user.

Vendor Response

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

Disclosure Timeline

    2015-09-08 - Vulnerability reported to vendor
    2015-11-10 - Coordinated public release of advisory

Credit

This vulnerability was discovered by:
    Steven Seeley of Source Incite