KLA10661 Multiple vulnerabillities in Microsoft Office

Multiple serious vulnerabilities have been found in Microsoft Office. Malicious users can exploit these vulnerabilities to execute arbitrary code or conduct XSS attack.

Below is a complete list of vulnerabilities

1. Improper memory objects handling can be exploited remotely via a specially designed file to execute arbitrary code;
2. Improper user-supplied web-requests sanitization at SharePoint can be exploited remotely via a specially designed user content to conduct cross-site-scripting;
3. An unknown vulnerability can be exploited remotely via a specially designed EPS file to execute arbitrary code.

Technical details

To exploit vulnerability (2) attacker must have ability to submit malicious content to a target site. In some conditions user content will not be sanitized. When user visits web page with malicious content? script could be run in security context of the user.

(3) could be exploited via specially designed EPS graphics contained in office document or when user inserts this graphics to office document. Also if Word is selected as default email reader (default) then attacker could send specially designed email contains malicious EPS graphics. In such conditions exploitations needs minimal users interaction (preview malicious email)

Original advisories

CVE-2015-2523

CVE-2015-2522

CVE-2015-2521

CVE-2015-2545

CVE-2015-2520

Exploitation

Public exploits exist for this vulnerability.

Malware exists for this vulnerability. Usually such malware is classified as Exploit. More details.

Related products

Microsoft-Office

Microsoft-Excel

CVE list

CVE-2015-2523 critical

CVE-2015-2522 warning

CVE-2015-2521 critical

CVE-2015-2545 critical

CVE-2015-2520 critical

KB list

3054813

3085487

3085501

3085502

3085543

3085483

3088502

3088501

3054995

3054987

3054993

3089664

3054932

3054965

3085526

Solution

Install necessary updates from the KB section, that are listed in your Windows Update (Windows Update usually can be accessed from the Control Panel)

Impacts

• ACE

Arbitrary code execution. Exploitation of vulnerabilities with this impact can lead to executing by abuser any code or commands at vulnerable machine or process.

• SB

Security bypass. Exploitation of vulnerabilities with this impact can lead to performing actions restricted by current security settings.

• XSS/CSS

Cross site scripting. Exploitation of vulnerabilities with this impact can lead to partial interception of information transmitted between user and site.

• SUI

Spoof user interface. Exploitation of vulnerabilities with this impact can lead to changes in user interface to beguile user into inaccurate behavior.

Affected Products

• Office 2007 Service Pack 3Excel 2007 Service Pack 3Office 2010 Service Pack 2Excel 2010 Service Pack 2Office 2013 Service Pack 1Excel 2013 Service Pack 1Office 2013 RT Service Pack 1Excel 2013 RT Service Pack 1Excel for Mac 2011Excel for Mac 2016Office Compatibility Pack  Service Pack 3Excel ViewerSharePoint Foundation 2013 Service Pack 1