Microsoft Skype for Business CVE-2017-11786 Privilege Escalation Vulnerability



Date Discovered

October 10, 2017


Microsoft Skype for Business is prone to a privilege-escalation vulnerability. Attackers can exploit this issue to gain elevated privileges.

Technologies Affected

  • Microsoft Lync 2013 (32-bit) SP1
  • Microsoft Lync 2013 (64-bit) SP1
  • Microsoft Skype for Business 2016 (32-bit)
  • Microsoft Skype for Business 2016 (64-bit)


Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy NIDS to monitor network traffic for signs of anomalous or suspicious activity. This may indicate exploit attempts or activity that results from successful exploits.

Do not accept or execute files from untrusted or unknown sources.
Users should be cautious when installing and running application from untrusted sources.

Do not follow links provided by unknown or untrusted sources.
Do not follow links provided by unknown or untrusted sources. Web users should be cautious about following links to websites that are provided by unfamiliar or suspicious sources. Filtering HTML from emails may help remove a possible vector for transmitting malicious links to users.

Updates are available. Please see the references or vendor advisory for more information.



Jerry Decime, Hewlett Packard Enterprise

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