SRC-2016-0042 : Microsoft Office Word OneTableDocumentStream Integer Underflow Information Disclosure Vulnerability



CVSS Score:

4.3, (AV:N/AC:M/Au:N/C:P/I:N/A:N)

Affected Vendors:


Affected Products:

Office Word

  • Microsoft Word 2007 Service Pack 3
  • Microsoft Office 2010 Service Pack 2 (32-bit editions)
  • Microsoft Office 2010 Service Pack 2 (64-bit editions)
  • Microsoft Office Compatibility Pack Service Pack 3
  • Microsoft Word for Mac 2011
  • Word Automation Services on Microsoft SharePoint Server 2010 Service Pack 2
  • Microsoft Office Web Apps 2010 Service Pack 2

Vulnerability Details:

This vulnerability allows remote attackers to disclose information on vulnerable installations of Microsoft Office Word. 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 a OneTableDocumentStream chunk during the processing of a specially crafted doc file. A data point value is used to calculate a size variable which can be underflowed before a heap allocation. During further processing, the allocated chunk is used as a source buffer during a memcpy operation leading to an out-of-bounds read condition. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of the current process.

Vendor Response:

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

Disclosure Timeline:

  • 2016-09-21 – Vulnerability reported to vendor
  • 2016-12-13 – Coordinated public release of advisory


This vulnerability was discovered by Steven Seeley of Source Incite