SRC-2016-0043 : Microsoft Office Word Array Indexing Out-Of-Bounds Read Information Disclosure Vulnerability

CVE ID:

CVE-2016-7291

CVSS Score:

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

Affected Vendors:

Microsoft

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 processing of a document file. A specially crafted doc file will lead to a read beyond the end of a heap buffer due to improper index calculation for array access before a copy operation. 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: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2016-7291

Disclosure Timeline:

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

Credit:

This vulnerability was discovered by Steven Seeley of Source Incite