Microsoft Skype for Business and Lync CVE-2018-8311 Remote Code Execution Vulnerability



Date Discovered

July 10, 2018


Microsoft Skype for Business and Lync are prone to a remote code-execution vulnerability. Successfully exploiting this issue may result in the execution of arbitrary code in the context of the current user. Failed exploit attempts will likely result in denial-of-service conditions.

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.

Implement multiple redundant layers of security.
Memory-protection schemes (such as nonexecutable stack and heap configurations and randomly mapped memory segments) will complicate exploits of memory-corruption vulnerabilities.

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



Ping Fan (Zetta) Ke of Valkyrie-X Security Research Group (VXRL)

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